As filed with the Securities and Exchange Commission on December 21, 2004

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

FORM S-3

PINNACLE WEST CAPITAL CORPORATION

400 North Fifth Street
Phoenix, Arizona 85004
(602) 250-1000
(Address, including zip code, and telephone number, including area code,
of registrant’s principal executive offices)

MATTHEW P. FEENEY
Snell & Wilmer L.L.P.
One Arizona Center
Phoenix, Arizona 85004
(602) 382-6239
(Name, address, including zip code, and telephone number,
including area code, of agent for service)

     Approximate date of commencement of proposed sale to the public: From time to time after the effective date of this Registration Statement, as determined by market conditions and other factors.

     If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

     If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. x

     If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

     If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

     If delivery of the prospectus is expected to be made pursuant to Rule 434, please check the following box. o

CALCULATION OF REGISTRATION FEE

          The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, or until this Registration Statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION
Dated December 21, 2004

Prospectus

PINNACLE WEST CAPITAL CORPORATION

$500,000,000

Debt Securities
Preferred Stock
Common Stock
Purchase Contracts
Units

     We may offer and sell these securities from time to time in one or more offerings. This prospectus provides you with a general description of the securities we may offer.

     Each time we sell these securities, we will provide a supplement to this prospectus that contains specific information about the offering and the terms of the securities. The supplement may also add, update, or change information contained in this prospectus. You should carefully read this prospectus and any supplement, as well as the documents incorporated by reference in this prospectus, before you invest in any of these securities.

     See “Risk Factors” beginning on page 3 of this prospectus to read about certain factors you should consider before investing in these securities.

     Our principal executive offices are located at 400 North Fifth Street, Phoenix, AZ 85004. Our telephone number is (602) 250-1000.

     Our common stock is listed on the New York Stock Exchange under the symbol “PNW.”

     Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.

     We may offer and sell these securities directly to purchasers, through agents, dealers, or underwriters as designated from time to time, or through a combination of these methods. Additional information on our plan of distribution can be found inside under “Plan of Distribution.” We will describe the plan of distribution for any securities in the relevant prospectus supplement. If any agents, dealers or underwriters are involved in the sale of any securities, the relevant prospectus supplement will set forth any applicable commissions or discounts.

     This prospectus may not be used to consummate sales of these securities unless accompanied by the applicable prospectus supplement.

The date of this prospectus is           ,       

TABLE OF CONTENTS

     Unless otherwise indicated, currency amounts in this prospectus and any prospectus supplement are stated in United States dollars (“$,” “dollars,” “U.S. dollars,” or “U.S.$”).

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RISK FACTORS

     Before purchasing our securities you should carefully consider the following risk factors as well as the other information contained in this prospectus and the information incorporated by reference in order to evaluate an investment in our securities. Although we have tried to discuss key factors in this prospectus, please be aware that other risks may prove to be important in the future. New risks may emerge at any time and we cannot predict such risks or estimate the extent to which they may affect our financial performance. The documents we file with the SEC after the date of this prospectus may contain additional risk factors, or updates to the risk factors discussed below, which you should consider. See “Where You Can Find More Information.”

     We cannot predict the outcome of the general rate case of Arizona Public Service Company (“APS”), our principal subsidiary, pending before the Arizona Corporation Commission (the “ACC”).

     On June 27, 2003, APS filed a request with the ACC to increase its annual retail electricity revenues by approximately $175.1 million, or 9.8%, effective July 1, 2004. On August 18, 2004, a substantial majority of the parties to the rate case, including APS, the ACC staff, the Residential Utility Consumer Office, other customer groups, and merchant power plant intervenors entered into an agreement that proposes terms under which the rate case would be settled (the “Agreement”). The Agreement is subject to ACC approval. Key financial components of the Agreement are as follows:

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     This general rate case, including the proposed settlement, is the key issue affecting our financial outlook. ACC hearings on the Agreement concluded on December 3, 2004. The parties are awaiting the issuance of a recommended opinion and order from the administrative law judge, after which the ACC is expected to consider the proposed settlement. We cannot predict the outcome of this matter.

     The procurement of wholesale power by APS without the ability to adjust retail rates could have an adverse impact on our business and financial results.

     Although the Rules allow retail customers to have access to competitive providers of energy and energy services, under the Rules, APS is the “provider of last resort” for standard-offer, full-service customers under rates that have been approved by the ACC. In the event of shortfalls of electricity due to unforeseen increases in load demand or generation or transmission outages, APS may need to purchase additional supplemental power in the wholesale spot market. At various times, prices in the spot wholesale market have significantly exceeded the amount included in APS’ current retail rates. There can be no assurance that APS would be able to fully recover the costs of this power. Although the proposed settlement of APS’ general rate case would, among other things, allow APS to recover purchased power costs, there can be no assurance that the settlement agreement will be approved by the ACC as proposed.

     Deregulation or restructuring of the electric industry may result in increased competition, which could have a significant adverse impact on our business and our financial results.

     Retail competition could have a significant adverse financial impact on us due to an impairment of assets, a loss of retail customers, lower profit margins or increased costs of capital. Under the Rules, as modified by the 1999 Settlement Agreement, APS was required to transfer all of its competitive electric assets and services to an unaffiliated party or parties or to a separate corporate affiliate or affiliates no later than December 31, 2002. To satisfy this requirement, APS had planned to transfer its generation assets to Pinnacle West Energy. Pursuant to an ACC order dated September 10, 2002, the ACC unilaterally modified the 1999 Settlement Agreement and directed APS to cancel any plans to divest interests in any of its generating assets. The ACC further established a requirement that APS solicit bids for certain estimated amounts of capacity and energy for periods beginning July 1, 2003. Pinnacle West Energy bid on and entered into contracts to supply most of APS’ requirements in the summer months through September 2006. In addition, as discussed above, a proposed settlement of APS’ general rate case would result in Pinnacle West Energy transferring a significant amount of generation assets to APS. These regulatory developments and legal challenges to the Rules have raised considerable uncertainty about the status and pace of retail electric competition and of electric restructuring in Arizona. Although some very limited retail competition existed in APS’ service area in 1999 and 2000, there are currently no active retail competitors offering unbundled energy or other utility services to APS’ customers. As a result, we cannot predict when, and the extent to which, additional competitors will re-enter APS’ service territory.

     As a result of changes in federal law and regulatory policy, competition in the wholesale electricity market has greatly increased due to a greater participation by traditional electricity suppliers, non-utility generators, independent power producers, and wholesale power marketers and brokers. This increased competition could affect our load forecasts, plans for power supply and wholesale energy sales and

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related revenues. As a result of the changing regulatory environment and the relatively low barriers to entry, we expect wholesale competition to increase. As competition continues to increase, our financial position and results of operations could be adversely affected.

     We are subject to complex government regulation that may have a negative impact on our business and our results of operations.

     We are, directly and through our subsidiaries, subject to governmental regulation that may have a negative impact on our business and results of operations. We are a “holding company” within the meaning of the Public Utility Holding Company Act of 1935 (“PUHCA”); however, we are exempt from the provisions of PUHCA (except Section 9(a)(2) thereof) by virtue of our filing of an annual exemption statement with the Securities and Exchange Commission (the “SEC”).

     APS is subject to comprehensive regulation by several federal, state and local regulatory agencies, which significantly influence its operating environment and may affect its ability to recover costs from utility customers. APS is required to have numerous permits, approvals and certificates from the agencies that regulate APS’ business. The FERC, the Nuclear Regulatory Commission (“NRC”), the Environmental Protection Agency (“EPA”), and the ACC regulate many aspects of our utility operations, including siting and construction of facilities, customer service and the rates that APS can charge customers. We believe the necessary permits, approvals and certificates have been obtained for APS’ existing operations. However, changes in regulations or the imposition of additional regulations could have an adverse impact on our results of operations. We are also unable to predict the impact on our business and operating results from pending or future regulatory activities of any of these agencies.

     We are subject to numerous environmental laws and regulations that may increase our cost of operations, impact our business plans, or expose us to environmental liabilities.

     We are subject to numerous environmental laws and regulations affecting many aspects of our present and future operations, including air emissions, water quality, wastewater discharges, solid waste, and hazardous waste. These laws and regulations can result in increased capital, operating, and other costs, particularly with regard to enforcement efforts focused on power plant emissions obligations. These laws and regulations generally require us to obtain and comply with a wide variety of environmental licenses, permits, inspections and other approvals. Both public officials and private individuals may seek to enforce applicable environmental laws and regulations. We cannot predict the outcome (financial or operational) of any related litigation that may arise.

     In addition, we may be a responsible party for environmental clean up at sites identified by a regulatory body. We cannot predict with certainty the amount and timing of all future expenditures related to environmental matters because of the difficulty of estimating clean-up costs. There is also uncertainty in quantifying liabilities under environmental laws that impose joint and several liability on all potentially responsible parties.

     We cannot be sure that existing environmental regulations will not be revised or that new regulations seeking to protect the environment will not be adopted or become applicable to us. Revised or additional regulations that result in increased compliance costs or additional operating restrictions, particularly if those costs are not fully recoverable from APS’ customers, could have a material adverse effect on our results of operations.

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     There are inherent risks in the operation of nuclear facilities, such as environmental, health and financial risks and the risk of terrorist attack.

     Through APS, we have an ownership interest in and operate, on behalf of a group of owners, the Palo Verde Nuclear Generating Station (“Palo Verde”), which is the largest nuclear electric generating facility in the United States. Palo Verde is subject to environmental, health and financial risks such as the ability to dispose of spent nuclear fuel, the ability to maintain adequate reserves for decommissioning, potential liabilities arising out of the operation of these facilities, and the costs of securing the facilities against possible terrorist attacks and unscheduled outages due to equipment and other problems. We maintain nuclear decommissioning trust funds and external insurance coverage to minimize our financial exposure to some of these risks; however, it is possible that damages could exceed the amount of insurance coverage.

     The NRC has broad authority under federal law to impose licensing and safety-related requirements for the operation of nuclear generation facilities. In the event of noncompliance, the NRC has the authority to impose fines or shut down a unit, or both, depending upon its assessment of the severity of the situation, until compliance is achieved. In addition, although we have no reason to anticipate a serious nuclear incident at Palo Verde, if an incident did occur, it could materially and adversely affect our results of operations or financial condition. A major incident at a nuclear facility anywhere in the world could cause the NRC to limit or prohibit the operation or licensing of any domestic nuclear unit.

     The operation of Palo Verde requires licenses that need to be periodically renewed and/or extended. We do not anticipate any problems renewing these licenses. However, as a result of potential terrorist threats and increased public scrutiny of utilities, the licensing process could result in increased licensing or compliance costs that are difficult or impossible to predict.

     The uncertain outcome regarding the creation of regional transmission organizations, or RTOs, and implementation of the FERC’s standard market design may materially impact our operations, cash flows or financial position.

     In a December 1999 order, the FERC established characteristics and functions that must be met by utilities in forming and operating RTOs. The characteristics for an acceptable RTO include independence from market participants, operational control over a region large enough to support efficient and nondiscriminatory markets and exclusive authority to maintain short-term reliability. Additionally, in a pending notice of proposed rulemaking, the FERC is considering implementing a standard market design for wholesale markets. On October 16, 2001, APS and other owners of electric transmission lines in the Southwest filed with the FERC a request for a declaratory order confirming that its proposal to form WestConnect RTO, LLC would satisfy the FERC’s requirements for the formation of an RTO. On October 10, 2002, the FERC issued an order finding that the WestConnect proposal, if modified to address specified issues, could meet the FERC’s RTO requirements and provide the basic framework for a standard market design for the Southwest. On September 15, 2003, the FERC issued an order granting clarification and rehearing, in part, of its prior orders. In particular, this order approved the use of a physical congestion management scheme, which is used to allocate transmission rights on congested lines, for WestConnect for an initial phase-in period. The FERC indicated that the WestConnect utilities and the appropriate regional state advisory committee should develop a market-based congestion management scheme for subsequent implementation. APS is now participating in a cost/benefit analysis of implementing WestConnect, the results of which are expected to be completed in 2005.

     If APS ultimately joins an RTO, APS could incur increased transmission-related costs and receive reduced transmission service revenues; APS may be required to expand its transmission system according to decisions made by the RTO rather than its internal planning process; and APS may experience other impacts on its operations, cash flows or financial position that will not be quantifiable until the final tariffs and other material terms of the RTO are known.

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     Recent events in the energy markets that are beyond our control may have negative impacts on our business.

     As a result of the energy crisis in California during the summer of 2001, the recent volatility of natural gas prices in North America, the filing of bankruptcy by the Enron Corporation, and investigations by governmental authorities into energy trading activities, companies generally in the regulated and unregulated utility businesses have been under an increased amount of public and regulatory scrutiny. The capital markets and rating agencies also have increased their level of scrutiny. We believe that we are in material compliance with all applicable laws, but it is difficult or impossible to predict or control what effect these or related issues may have on our business or our access to the capital markets.

     Our results of operations can be adversely affected by milder weather.

     Weather conditions directly influence the demand for electricity and affect the price of energy commodities. Electric power demand is generally a seasonal business. In Arizona, demand for power peaks during the hot summer months, with market prices also peaking at that time. As a result, our overall operating results fluctuate substantially on a seasonal basis. In addition, we have historically sold less power, and consequently earned less income, when weather conditions are milder. As a result, unusually mild weather could diminish our results of operations and harm our financial condition.

     Our cash flow largely depends on the performance of our subsidiaries.

     We conduct our operations primarily through subsidiaries. Substantially all of our consolidated assets are held by such subsidiaries. Accordingly, our cash flow is dependent upon the earnings and cash flows of these subsidiaries and their distributions to us. The subsidiaries are separate and distinct legal entities and have no obligation to make distributions to us.

     The debt agreements of some of our subsidiaries may restrict their ability to pay dividends, make distributions or otherwise transfer funds to us. As part of the ACC’s approval of a $500 million financing arrangement between APS and Pinnacle West Energy, an ACC order requires APS to maintain a common equity ratio of at least 40% and does not allow APS to pay common dividends if the payment would reduce its common equity below that threshold. As defined in the ACC financing order approving the arrangement, common equity ratio is common equity divided by common equity plus long-term debt, including current maturities of long-term debt. At September 30, 2004, APS’ common equity ratio was approximately 46%.

     The debt securities will be structurally subordinated to the debt securities and other obligations of our subsidiaries.

     Because we are structured as a holding company, all existing and future debt and other liabilities of our subsidiaries will be effectively senior in right of payment to our debt securities. None of the indentures under which we or our subsidiaries may issue debt securities limits our ability or the ability of our subsidiaries to incur additional debt in the future. The assets and cash flows of our subsidiaries will be available, in the first instance, to service their own debt and other obligations. Our ability to have the benefit of their assets and cash flows, particularly in the case of any insolvency or financial distress affecting our subsidiaries, would arise only through our equity ownership interests in our subsidiaries and only after their creditors have been satisfied.

     If we are not able to access capital at competitive rates, our ability to implement our financial strategy will be adversely affected.

     We rely on access to short-term money markets, longer-term capital markets and the bank markets as a significant source of liquidity and for capital requirements not satisfied by the cash flow from our operations. We believe that we will maintain sufficient access to these financial markets based upon current credit ratings. However, certain market disruptions or a downgrade of our credit ratings may

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increase our cost of borrowing or adversely affect our ability to access one or more financial markets. Such disruptions could include:

     Changes in economic conditions could result in higher interest rates, which would increase our interest expense on our debt and reduce funds available to us for our current plans. Additionally, an increase in our leverage could adversely affect us by:

     A significant reduction in our credit ratings could materially and adversely affect our business, financial condition and results of operations.

     We cannot be sure that any of our current ratings will remain in effect for any given period of time or that a rating will not be lowered or withdrawn entirely by a rating agency if, in its judgment, circumstances in the future so warrant. Any downgrade could increase our borrowing costs, which would diminish our financial results. We would likely be required to pay a higher interest rate in future financings, and our potential pool of investors and funding sources could decrease. In addition, borrowing costs under certain of our existing credit facilities depend on our credit ratings. A downgrade could also require us to provide additional support in the form of letters of credit or cash or other collateral to various counterparties. If our short-term ratings were to be lowered, it could limit our access to the commercial paper market. We note that the ratings from rating agencies are not recommendations to buy, sell or hold our securities and that each rating should be evaluated independently of any other rating.

     The use of derivative contracts in the normal course of our business and changing interest rates and market conditions could result in financial losses that negatively impact our results of operations.

     Our operations include managing market risks related to commodity prices and, subject to specified risk parameters, engaging in marketing and trading activities intended to profit from market price movements. We are exposed to the impact of market fluctuations in the price and transportation costs of electricity, natural gas, coal, and emissions allowances and credits. We have established procedures to manage risks associated with these market fluctuations by utilizing various commodity derivatives, including exchange-traded futures and options and over-the-counter forwards, options, and swaps. As

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part of our overall risk management program, we enter into derivative transactions to hedge purchases and sales of electricity, fuels, and emissions allowances and credits. The changes in market value of such contracts have a high correlation to price changes in the hedged commodity.

     We are exposed to losses in the event of nonperformance or nonpayment by counterparties. We use a risk management process to assess and monitor the financial exposure of all counterparties. Despite the fact that the majority of trading counterparties are rated as investment grade by the rating agencies, there is still a possibility that one or more of these companies could default, resulting in a material adverse impact on our earnings for a given period.

     Changing interest rates will affect interest paid on variable-rate debt and interest earned by our pension plan and nuclear decommissioning trust funds. Our policy is to manage interest rates through the use of a combination of fixed-rate and floating-rate debt. The pension plan is also impacted by the discount rate, which is the interest rate used to discount future pension obligations. Continuation of recent decreases in the discount rate would result in increases in pension costs, cash contributions, and charges to other comprehensive income. The pension plan and nuclear decommissioning trust funds also have risks associated with changing market values of equity investments. A significant portion of the pension costs and all of the nuclear decommissioning costs are recovered in regulated electricity prices.

     Actual results could differ from estimates used to prepare our financial statements.

     In preparing our financial statements in accordance with accounting principles generally accepted in the United States of America, management must often make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and related disclosures at the date of the financial statements and during the reporting period. Some of those judgments can be subjective and complex, and actual results could differ from those estimates. We consider the following accounting policies to be our most critical because of the uncertainties, judgments and complexities of the underlying accounting standards and operations involved.

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     The market price of our common stock may be volatile.

     The market price of our common stock could be subject to significant fluctuations in response to factors such as the following, some of which are beyond our control:

     In addition, the stock market in general has experienced volatility that has often been unrelated to the operating performance of a particular company. These broad market fluctuations may adversely affect the market price of our common stock.

     Our common stock price could be affected because a substantial number of our shares could be available for sale in the future.

     Sales in the public market of a substantial number of shares of common stock could depress the market price of the common stock and could impair our ability to raise capital through the sale of additional equity securities. Because of the number of shares of our common stock that we are authorized to issue under our articles of incorporation, a substantial number of shares of our common stock could be available for future sale.

     We may enter into credit and other agreements from time to time that restrict our ability to pay dividends.

     Payment of dividends on our common stock may be restricted by credit and other agreements entered into by us from time to time. At September 30, 2004, there were no material restrictions on our ability to pay dividends under any such agreement.

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     Certain provisions of our articles of incorporation and bylaws and of Arizona law make it more difficult for shareholders to change the composition of our board and may discourage takeover attempts that could be beneficial to us and our shareholders.

     Certain provisions of our articles of incorporation and bylaws and of Arizona law make it more difficult for shareholders to change the composition of our board and may discourage unsolicited attempts to acquire us, which could preclude our shareholders from receiving a change of control premium. These provisions include the following:

     In addition, we have adopted a shareholder rights plan that may have the effect of discouraging unsolicited takeover proposals, including takeover proposals that could result in a premium over the market price of our common stock.

     While these provisions have the effect of encouraging persons seeking to acquire control of us to negotiate with our Board of Directors, they could enable the board to hinder or frustrate a transaction that some, or a majority, of our shareholders might believe to be in their best interests and, in that case, may prevent or discourage attempts to remove and replace incumbent directors. For more information, see “Description of Common Stock-Certain Anti-takeover Effects” in this prospectus.

ABOUT THIS PROSPECTUS

     This prospectus is part of a shelf registration statement that we filed with the SEC utilizing a “shelf” registration process. Under this shelf process, we may offer up to $500,000,000 aggregate initial offering price of the debt securities, preferred stock, common stock, purchase contracts and units

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described in this prospectus in one or more offerings. In this prospectus we will refer to the debt securities, preferred stock, common stock, purchase contracts and units collectively as the “securities.” This prospectus provides you with a general description of the securities we may offer. Each time we offer securities, we will provide you with a prospectus supplement and, if applicable, a pricing supplement. The prospectus supplement and any applicable pricing supplement will describe the specific terms of the securities being offered. The prospectus supplement and any applicable pricing supplement may also add to, update or change the information in this prospectus. If there is any inconsistency between the information in this prospectus and in any supplement, you should rely on the information in the supplement. In addition, the registration statement filed with the SEC includes exhibits that provide more details about the securities. Please carefully read this prospectus, the applicable prospectus supplement and any applicable pricing supplement, together with the information contained in the documents referred to under the heading “Where You Can Find More Information.” You should assume that the information appearing in this prospectus and any supplement to this prospectus is accurate only as of the dates on their covers. Our business, financial condition, results of operations, and prospects may have changed since those dates.

FORWARD-LOOKING STATEMENTS

     This prospectus, any accompanying prospectus supplement, and the additional information described under the heading “Where You Can Find More Information” may contain forward-looking statements within the meaning of the safe harbor of the Private Securities Litigation Reform Act of 1995. These statements are subject to risks and uncertainties and are based on the beliefs and assumptions of our management, based on information currently available to our management. When we use words such as “believes,” “expects,” “anticipates,” “intends,” “plans,” “estimates,” “predicts,” “should,” or similar expressions, we are making forward-looking statements.

     Forward-looking statements are not guarantees of performance. They involve risks, including those described under “Risk Factors” above, uncertainties, and assumptions. Our future results may differ materially from those expressed in these forward-looking statements. Many of the factors that will determine these results are beyond our ability to control or predict. Except to the extent required by federal securities laws, we undertake no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise. These factors include, but are not limited to:

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     You are cautioned not to put undue reliance on any forward-looking statements. We claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995 for any forward-looking statements contained in this prospectus, including in the information incorporated by reference in this prospectus, and any prospectus supplement.

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WHERE YOU CAN FIND MORE INFORMATION

Available Information

     We file annual, quarterly, and current reports, and other information with the SEC. Our SEC filings are available to the public over the Internet at the SEC’s web site: http://www.sec.gov. You may also read and copy any document we file at the SEC’s public reference room, which is located at Room 1024, Judiciary Plaza, 450 Fifth Street NW, Washington, D.C. 20549. You may call the SEC at 1-800-SEC-0330 for further information on the public reference room. Reports and other information concerning us can also be inspected and copied at the offices of the New York Stock Exchange at 20 Broad Street, New York, New York 10005, and the Pacific Stock Exchange at 301 Pine Street, San Francisco, California 94104. Our filings with the SEC are also available on our own web site at http://www.pinnaclewest.com. The other information on our web site is not part of this prospectus or any prospectus supplement.

Incorporation By Reference

     The SEC allows us to incorporate by reference the information we file with them, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus, and later information that we file with the SEC will automatically update and supersede this information. We incorporate by reference the documents listed below, all documents we file with the SEC under Sections 13(a), 13(c), 14, or 15(d) of the Securities Exchange Act of 1934 after the date of the initial registration statement to which this prospectus relates and prior to the effectiveness of the registration statement, and any future filings we make with the SEC under Sections 13(a), 13(c), 14, or 15(d) of the Securities Exchange Act of 1934 until all securities are sold under this prospectus, excluding, in each case, information deemed furnished and not filed.

     You may request a copy of these filings and will receive a copy of these filings, at no cost, by writing or telephoning us at the following address:

Pinnacle West Capital Corporation
Office of the Secretary
Station 9068
P.O. Box 53999
Phoenix, Arizona 85072-3999
(602) 250-3252

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THE COMPANY

     We own all of the outstanding common stock of APS. APS was incorporated in 1920 under the laws of Arizona. APS is a vertically-integrated electric utility that provides either retail or wholesale electric service to most of the State of Arizona. Through APS’ marketing and trading division, APS generates, sells and delivers electricity to wholesale customers in the western United States. APS’ marketing and trading division also sells, in the wholesale market, the generation output of our subsidiary, Pinnacle West Energy, that is not needed for APS’ native load, which includes loads for retail customers and traditional cost-of-service wholesale customers. The marketing and trading division focuses primarily on managing APS’ purchased power and fuel risks in connection with APS’ costs of serving retail customer energy requirements. APS does not distribute any products. APS currently has more than 931,500 customers. Our principal executive offices are located at 400 North Fifth Street, Phoenix, Arizona 85004, and the telephone number is 602-250-1000.

     Our other major subsidiaries are:

RATIO OF EARNINGS TO FIXED CHARGES

     The following table shows our consolidated ratio of earnings to fixed charges and our consolidated ratio of earnings to combined fixed charges and preferred dividends (we have reclassified certain prior year amounts to conform to the current year presentation):

     The ratio of earnings to fixed charges was computed by dividing earnings by fixed charges. For this purpose, earnings consist of pre-tax income from continuing operations excluding extraordinary items and cumulative effect of change in accounting for derivatives, plus the amount of fixed charges as defined below. Fixed charges consist of: expensed interest; amortization of debt discount, premium and expense; and an estimate of interest implicit in rentals.

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     The ratio of earnings to combined fixed charges and preferred dividends was computed by dividing earnings by the sum of fixed charges and preferred dividends. For this purpose, earnings consist of pre-tax income from continuing operations excluding extraordinary items and cumulative effect of change in accounting for derivatives, plus the amount of combined fixed charges and preferred dividends as defined below. Combined fixed charges and preferred dividends consist of: expensed interest; amortization of debt discount, premium and expense; an estimate of interest implicit in rentals; and preferred stock dividend requirements of majority-owned subsidiaries increased to reflect our pre-tax earnings requirement.

USE OF PROCEEDS

     We intend to use the proceeds from the sale of these securities for general corporate purposes, which may include the repayment of indebtedness, capital expenditures, the funding of working capital, acquisitions and stock repurchases and/or capital infusions into one or more of our subsidiaries for any of those purposes. The specific use of proceeds from the sale of securities will be set forth in the prospectus supplement relating to each offering of these securities.

GENERAL DESCRIPTION OF THE SECURITIES

     We, directly or through agents, dealers or underwriters that we designate, may offer and sell, from time to time, up to $500,000,000 (or the equivalent in one or more foreign currencies or currency units) aggregate initial offering price of:

     We may offer and sell these securities either individually or as units consisting of one or more of these securities, each on terms to be determined at the time of sale. We may issue debt securities and/or shares of preferred stock that are exchangeable for and/or convertible into common stock or any of the other securities that may be sold under this prospectus. When particular securities are offered, a supplement to this prospectus will be delivered with this prospectus, which will describe the terms of the offering and sale of the offered securities.

DESCRIPTION OF DEBT SECURITIES

General

     The following description highlights the general terms of the debt securities. When we offer debt securities in the future, the prospectus supplement will explain the particular terms of those securities and the extent to which any of these general provisions will not apply.

     We can issue an unlimited amount of debt securities under the indentures listed below. We can issue debt securities from time to time and in one or more series as determined by us. In addition, we can issue debt securities of any series with terms different from the terms of debt securities of any other series and the terms of particular debt securities within any series may differ from each other, all without

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the consent of the holders of previously issued series of debt securities. The debt securities of each series will be our direct, unsecured obligations. The debt securities may be issued in one or more new series under:

     As of September 30, 2004, there was outstanding $300 million of our 6.40% Notes due 2006 and $165 million of our Floating Rate Senior Notes due 2005 under the senior debt securities indenture described above.

     As of September 30, 2004, there was no debt outstanding under the subordinated debt securities indenture.

     Because we are structured as a holding company, all existing and future indebtedness and other liabilities of our subsidiaries will be effectively senior in right of payment to our debt securities, whether senior debt securities or subordinated debt securities. None of the above Indentures limits our ability or the ability of our subsidiaries to incur additional indebtedness in the future. The assets and cash flows of our subsidiaries will be available, in the first instance, to service their own debt and other obligations and our ability to have the benefit of their assets and cash flows, particularly in the case of any insolvency or financial distress affecting our subsidiaries, would arise only through our equity ownership interests in our subsidiaries and only after their creditors had been satisfied. As of September 30, 2004, our subsidiaries, principally APS, had approximately $2.8 billion of debt outstanding.

     We have summarized selected provisions of the Indentures below. The summary is not complete. We have filed the senior and subordinated Indentures and the forms of the convertible Indentures as exhibits to the registration statement. You should read the Indentures in their entirety, including the definitions of certain terms, together with this prospectus and the prospectus supplement before you make any investment decision. Although separate Indentures are used for subordinated debt securities, senior debt securities, convertible subordinated debt securities and convertible senior debt securities, references to the “Indenture” and the description of the “Indenture” in this section apply to all Indentures, unless otherwise noted.

     You should refer to the prospectus supplement attached to this prospectus for the following information about a new series of debt securities:

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     We may sell the debt securities at a substantial discount below their principal amount. The prospectus supplement may describe special federal income tax considerations that apply to debt securities sold at an original issue discount or to debt securities that are denominated in a currency other than United States dollars.

     Unless the applicable prospectus supplement specifies otherwise, the debt securities will not be listed on any securities exchange.

     Other than the protections described in this prospectus and in the prospectus supplement, holders of debt securities would not be protected by the covenants in the Indenture from a highly-leveraged transaction.

Subordination

     Each Indenture relating to the subordinated debt securities states that, unless otherwise provided in a supplemental indenture or a board resolution, the debt securities will be subordinate to all senior debt. This is true whether the senior debt is outstanding as of the date of the Indenture or is incurred afterwards. The balance of the information under this heading assumes that a supplemental indenture or a board resolution results in a series of debt securities being subordinated obligations.

     The Indenture states that we cannot make payments of principal, premium, or interest on the subordinated debt if:

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     The Indenture provides that we must pay all senior debt in full before the holders of the subordinated debt securities may receive or retain any payment if our assets are distributed to our creditors upon any of the following:

     The Indenture provides that when all amounts owing on the senior debt are paid in full, the holders of the subordinated debt securities will be subrogated to the rights of the holders of senior debt to receive payments or distributions applicable to senior debt.

     The Indenture defines senior debt as the principal, premium, interest and any other payment due under any of the following, whether outstanding at the date of the Indenture or thereafter incurred, created or assumed:

     However, the preceding will not be considered senior debt if the document creating the debt or the assumption or guarantee of the debt states that it is not superior to or that it is on equal footing with the subordinated debt securities.

     The Indenture does not limit the aggregate amount of senior debt that we may issue. As of September 30, 2004, our outstanding senior debt (excluding the debt of our subsidiaries) was approximately $478 million.

Convertibility

     No series of debt securities, whether senior or subordinated, will be convertible into, or exchangeable for, other securities or property except as set forth in the applicable prospectus supplement. You should refer to the prospectus supplement that accompanies this prospectus for a description of the specific conversion provisions and terms of any series of convertible debt securities that we may offer by that prospectus supplement. These terms and provisions may include:

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Form, Exchange, and Transfer

     Each series of debt securities will be issuable only in fully registered form and without coupons. In addition, unless otherwise specified in a prospectus supplement, the debt securities will be issued in denominations of $1,000 and multiples of $1,000. We, the trustee, and any of our agents may treat the registered holder of a debt security as the absolute owner for the purpose of making payments, giving notices, and for all other purposes.

     The holders of debt securities may exchange them for any other debt securities of the same series, in authorized denominations and equal principal amount. However, this type of exchange will be subject to the terms of the Indenture and any limitations that apply to global securities.

     A holder may transfer debt securities by presenting the endorsed security at the office of a security registrar or at the office of any transfer agent we designate. The holder will not be charged for any exchange or registration of transfer, but we may require payment to cover any tax or other governmental charge in connection with the transaction. We have appointed the trustee under each Indenture as security registrar. A prospectus supplement will name any transfer agent we designate for any debt securities if different from the security registrar. We may designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts at any time, except that we will maintain a transfer agent in each place of payment for debt securities.

     If the debt securities of any series are to be redeemed in part, we will not be required to do any of the following:

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Payment and Paying Agents

     Unless otherwise indicated in the applicable prospectus supplement, we will pay interest on a debt security on any interest payment date to the person in whose name the debt security is registered.

     Unless otherwise indicated in the applicable prospectus supplement, the principal, premium, and interest on the debt securities of a particular series will be payable at the office of the paying agents that we may designate. However, we may pay any interest by check mailed to the address, as it appears in the security register, of the person entitled to that interest. Also, unless otherwise indicated in the applicable prospectus supplement, the corporate trust office of the trustee in The City of New York will be our sole paying agent for payments with respect to debt securities of each series. Any other paying agent that we initially designate for the debt securities of a particular series will be named in the applicable prospectus supplement. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts, except that we will maintain a paying agent in each place of payment for the debt securities of a particular series.

     All money that we pay to a paying agent for the payment of the principal, premium, or interest on any debt security that remains unclaimed at the end of two years after the principal, premium, or interest has become due and payable will be repaid to us, and the holder of the debt security may look only to us for payment.

Consolidation, Merger, and Sale Of Assets

     Unless otherwise indicated in the applicable prospectus supplement, we may not:

unless the following conditions are met:

     Upon any merger, consolidation, or transfer or lease of properties, the successor person will be substituted for us under the Indenture, and, thereafter, except in the case of a lease, we will be relieved of all obligations and covenants under the Indenture and the debt securities.

Events of Default

     Each of the following will be an event of default under the Indenture with respect to debt securities of any series:

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     If an event of default occurs and is continuing, other than an event of default relating to bankruptcy, insolvency, or reorganization, either the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of the affected series may declare the principal amount of the debt securities of that series to be due and payable immediately. In the case of any debt security that is an original issue discount security or the principal amount of which is not then determinable, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series may declare the portion of the principal amount of the debt security specified in the terms of such debt security to be immediately due and payable upon an event of default.

     If an event of default involving bankruptcy, insolvency, or reorganization occurs, the principal amount of all the debt securities of the affected series will automatically, and without any action by the trustee or any holder, become immediately due and payable. After any acceleration, but before a judgment or decree based on acceleration, the holders of a majority in aggregate principal amount of the outstanding debt securities of that series may rescind and annul the acceleration if all events of default, other than the non-payment of accelerated principal, have been cured or waived as provided in the Indenture.

     The trustee will be under no obligation to exercise any of its rights or powers under the Indenture at the request or direction of any of the holders, unless the holders have offered the trustee reasonable indemnity. Subject to provisions for the indemnification of the trustee, the holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method, and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series.

     No holder of a debt security of any series will have any right to institute any proceeding under the Indenture, or for the appointment of a receiver or a trustee, or for any other remedy under the Indenture, unless:

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     The limitations provided above do not apply to a suit instituted by a holder of a debt security for the enforcement of payment of the principal, premium, or interest on the debt security on or after the applicable due date.

     We are required to furnish to the trustee annually a certificate of various officers stating whether or not we are in default in the performance or observance of any of the terms, provisions, and conditions of the Indenture and, if so, specifying all known defaults.

Modification and Waiver

     In limited cases, we and the trustee may make modifications and amendments to the Indenture without the consent of the holders of any series of debt securities. We and the trustee may also make modifications and amendments to the Indenture with the consent of the holders of not less than 66 2/3% in aggregate principal amount of the outstanding debt securities of each series affected by the modification or amendment. However, without the consent of the holder of each outstanding debt security affected, no modification or amendment may:

     In general, compliance with certain restrictive provisions of the Indenture may be waived by the holders of not less than 66-2/3% in aggregate principal amount of the outstanding debt securities of any series. The holders of a majority in aggregate principal amount of the outstanding debt securities of any series may waive any past default under the Indenture, except:

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     In determining whether the holders of the requisite principal amount of the outstanding debt securities have given or taken any direction, notice, consent, waiver, or other action under the Indenture as of any date:

     If debt securities have been fully defeased or if we have deposited money with the trustee to redeem debt securities, they will not be considered outstanding.

     Except in limited circumstances, we will be entitled to set any day as a record date for the purpose of determining the holders of outstanding debt securities of any series entitled to give or take any direction, notice, consent, waiver, or other action under the Indenture. In limited circumstances, the trustee will be entitled to set a record date for action by holders. If a record date is set for any action to be taken by holders of a particular series, the action may be taken only by persons who are holders of outstanding debt securities of that series on the record date. To be effective, the action must be taken by holders of the requisite principal amount of the debt securities within a specified period following the record date. For any particular record date, this period will be 180 days or any other shorter period that we may specify. The period may be shortened or lengthened, but not beyond 180 days.

Defeasance and Covenant Defeasance

     We may elect to have the provisions of the Indenture relating to defeasance and discharge of indebtedness, or defeasance of restrictive covenants in the Indenture, applied to the debt securities of any series, or to any specified part of a series. The prospectus supplement used in connection with the offering of any debt securities will state whether we can make these elections for that series.

     Defeasance and Discharge

     We will be discharged from all of our obligations with respect to the debt securities of a series if we deposit with the trustee money in an amount sufficient to pay the principal, premium, and interest on the debt securities of that series when due in accordance with the terms of the Indenture and the debt securities. We can also deposit securities that will provide the necessary monies. However, we will not be discharged from the obligations to exchange or register the transfer of debt securities, to replace stolen, lost, or mutilated debt securities, to maintain paying agencies, and to hold moneys for payment in trust. The defeasance or discharge may occur only if we deliver to the trustee an opinion of counsel stating that we have received from, or there has been published by, the United States Internal Revenue Service a ruling, or there has been a change in tax law, in either case to the effect that holders of such debt securities:

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     Defeasance of Covenants

     We may elect to omit compliance with restrictive covenants in the Indenture and any additional covenants that may be described in the applicable prospectus supplement for a series of debt securities. This election will preclude some actions from being considered defaults under the Indenture for the applicable series. In order to exercise this option, we will be required to deposit, in trust for the benefit of the holders of debt securities, funds in an amount sufficient to pay the principal, premium and interest on the debt securities of the applicable series. We may also deposit securities that will provide the necessary monies. We will also be required to deliver to the trustee an opinion of counsel to the effect that holders of the debt securities will not recognize gain or loss for federal income tax purposes as a result of such deposit and defeasance of certain obligations and will be subject to federal income tax on the same amount, in the same manner and at the same times as would have been the case if the deposit and defeasance were not to occur. If we exercise this option with respect to any debt securities and the debt securities are declared due and payable because of the occurrence of any event of default, the amount of funds deposited in trust would be sufficient to pay amounts due on the debt securities at the time of their respective stated maturities but may not be sufficient to pay amounts due on the debt securities on any acceleration resulting from an event of default. In that case, we would remain liable for the additional payments.

Governing Law

     The law of the State of New York will govern the Indenture and the debt securities.

Global Securities

     Some or all of the debt securities of any series may be represented, in whole or in part, by one or more global securities, which will have an aggregate principal amount equal to that of the debt securities they represent. We will register each global security in the name of a depositary or nominee identified in a prospectus supplement and deposit the global security with the depositary or nominee. Each global security will bear a legend regarding the restrictions on exchanges and registration of transfer referred to below and other matters specified in a supplemental indenture to the Indenture.

     No global security may be exchanged for debt securities registered, and no transfer of a global security may be registered, in the name of any person other than the depositary for the global security or any nominee of the depositary, unless:

     We will register all securities issued in exchange for a global security or any portion of a global security in the names specified by the depositary.

     As long as the depositary or its nominee is the registered holder of a global security, the depositary or nominee will be considered the sole owner and holder of the global security and the debt

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securities that it represents. Except in the limited circumstances referred to above, owners of beneficial interests in a global security will not:

     We will make all payments of principal, premium, and interest on a global security to the depositary or its nominee. The laws of some jurisdictions require that purchasers of securities take physical delivery of securities in definitive form. These laws make it difficult to transfer beneficial interests in a global security.

     Ownership of beneficial interests in a global security will be limited to institutions that have accounts with the depositary or its nominee, referred to as Participants, and to persons that may hold beneficial interests through Participants. In connection with the issuance of any global security, the depositary will credit, on its book-entry registration and transfer system, the respective principal amounts of debt securities represented by the global security to the accounts of its Participants. Ownership of beneficial interests in a global security will only be shown on records maintained by the depositary or the Participant. Likewise, the transfer of ownership interests will be effected only through the same records. Payments, transfers, exchanges, and other matters relating to beneficial interests in a global security may be subject to various policies and procedures adopted by the depositary from time to time. Neither we, the trustee, nor any of our agents will have responsibility or liability for any aspect of the depositary’s or any Participant’s records relating to, or for payments made on account of, beneficial interests in a global security, or for maintaining, supervising, or reviewing any records relating to the beneficial interests.

Regarding the Trustee

     The Bank of New York is the trustee under our Indentures relating to the senior debt securities and the convertible senior debt securities and our Indentures relating to the subordinated debt securities and the convertible subordinated debt securities. It is also trustee of our pension plan and under various indentures covering securities issued by APS or on APS’ behalf. We and our affiliates maintain normal commercial and banking relationships with The Bank of New York, including The Bank of New York serving as transfer agent and registrar for our common stock. In the future The Bank of New York and its affiliates may provide banking, investment and other services to us and our affiliates.

DESCRIPTION OF PREFERRED STOCK

     We may issue, from time to time, shares of one or more series of our preferred stock. The following description sets forth certain general terms and provisions of the preferred stock to which any prospectus supplement may relate. The particular terms of any series of preferred stock and the extent, if any, to which these general provisions may apply to the series of preferred stock offered will be described in the prospectus supplement relating to that preferred stock.

     The following summary of provisions of the preferred stock does not purport to be complete and is subject to, and is qualified in its entirety by reference to, the provisions of our articles of incorporation, bylaws, and the amendment to our articles relating to a specific series of the preferred stock (the “statement of preferred stock designations”), which will be in the form filed as an exhibit to, or incorporated by reference in, the registration statement of which this prospectus is a part. Before

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investing in any series of our preferred stock, you should read our articles, bylaws and the relevant statement of preferred stock designations.

General

     Under our articles of incorporation, we have the authority to issue up to 10,000,000 shares of preferred stock. No shares of preferred stock are currently outstanding. 4,400,000 shares of preferred stock are reserved for issuance under our shareholders rights plan. See “Description of Common Stock—Certain Anti-takeover Effects—Shareholder Rights Plan.” Our Board of Directors is authorized to issue shares of preferred stock, in one or more series, and to fix for each series voting powers and those preferences and relative, participating, optional or other special rights and those qualifications, limitations or restrictions as are permitted by the Arizona Business Corporation Act (the “ABCA”).

     Our Board of Directors is authorized to determine the terms for each series of preferred stock, and the prospectus supplement will describe the terms of any series of preferred stock being offered, including:

Dividends

     Holders of shares of preferred stock shall be entitled to receive, when and as declared by our Board of Directors out of our funds legally available therefor, a cash dividend payable at the dates and at the rates, if any, per share as set forth in the applicable prospectus supplement.

Convertibility

     No series of preferred stock will be convertible into, or exchangeable for, other securities or property except as set forth in the applicable prospectus supplement.

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Redemption and Sinking Fund

     No series of preferred stock will be redeemable or receive the benefit of a sinking fund except as set forth in the applicable prospectus supplement.

Liquidation Rights

     Unless otherwise set forth in the applicable prospectus supplement, in the event of our liquidation, dissolution or winding up, the holders of shares of each series of preferred stock are entitled to receive distributions out of our assets available for distribution to stockholders, before any distribution of assets is made to holders of (i) any other shares of preferred stock ranking junior to that series of preferred stock as to rights upon liquidation and (ii) shares of common stock. The amount of liquidating distributions received by holders of preferred stock will generally equal the liquidation preference specified in the applicable prospectus supplement for that series of preferred stock, plus any dividends accrued and accumulated but unpaid to the date of final distribution. The holders of each series of preferred stock will not be entitled to receive the liquidating distribution of, plus such dividends on, those shares until the liquidation preference of any shares of our capital stock ranking senior to that series of the preferred stock as to the rights upon liquidation shall have been paid or set aside for payment in full.

     If upon our liquidation, dissolution or winding up, the amounts payable with respect to the preferred stock, and any other preferred stock ranking as to any distribution on a parity with the preferred stock are not paid in full, then the holders of the preferred stock and the other parity preferred stock will share ratably in any distribution of assets in proportion to the full respective preferential amount to which they are entitled. Unless otherwise specified in a prospectus supplement for a series of preferred stock, after payment of the full amount of the liquidating distribution to which they are entitled, the holders of shares of preferred stock will not be entitled to any further participation in any distribution of our assets. Neither a consolidation or merger of us with another corporation nor a sale of securities shall be considered a liquidation, dissolution or winding up of us.

Voting Rights

     The holders of each series of preferred stock we may issue will have no voting rights, except as required by law and as described below or in the applicable prospectus supplement. Our Board of Directors may, upon issuance of a series of preferred stock, grant voting rights to the holders of that series, including rights to elect additional board members if we fail to pay dividends in a timely fashion.

     Arizona law provides for certain voting rights for holders of a class of stock, even if the stock does not have other voting rights. Thus, the holders of all shares of a class, would be entitled to vote on any amendment to our articles of incorporation that would:

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     If the proposed amendment would affect a series of the class, but not the entire class, in one or more of the ways described in the bullets above, then the shares of the affected series will have the right to vote on the amendment as a separate voting group. However, if a proposed amendment that would entitle two or more series of the class to vote as separate voting groups would affect those series in the same or a substantially similar way, the shares of all the series so affected must vote together as a single voting group on the proposed amendment.

     Unless the articles of incorporation, Arizona law or the Board of Directors would require a greater vote or unless the articles or Arizona law would require a different quorum, if an amendment to the articles would allow the preferred stock or one or more series of the preferred stock to vote as voting groups, the vote required by each voting group would be:

     Arizona law may also require that the preferred stock be entitled to vote on certain other extraordinary transactions.

Miscellaneous

     The holders of our preferred stock will have no preemptive rights. All shares of preferred stock being offered by the applicable prospectus supplement will be fully paid and not liable to further calls or assessment by us. If we should redeem or otherwise reacquire shares of our preferred stock, then these shares will resume the status of authorized and unissued shares of preferred stock undesignated as to series, and will be available for subsequent issuance. There are no restrictions on repurchase or redemption of the preferred stock while there is any arrearage on sinking fund installments except as may be set forth in an applicable prospectus supplement. Payment of dividends on any series of preferred stock may be restricted by loan agreements, indentures and other transactions entered into by us. Any material contractual restrictions on dividend payments will be described or incorporated by reference in the applicable prospectus supplement.

     When we offer to sell a series of preferred stock, we will describe the specific terms of the series in the applicable prospectus supplement. If any particular terms of a series of preferred stock described in a prospectus supplement differ from any of the terms described in this prospectus, then the terms described in the applicable prospectus supplement will be deemed to supersede the terms described in this prospectus.

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No Other Rights

     The shares of a series of preferred stock will not have any preferences, voting powers or relative, participating, optional or other special rights except as set forth above or in the applicable prospectus supplement, our articles of incorporation or the applicable statement of preferred stock designations or as otherwise required by law.

Transfer Agent and Registrar

     The transfer agent and registrar for each series of preferred stock will be designated in the applicable prospectus supplement.

DESCRIPTION OF COMMON STOCK

     We may issue, from time to time, shares of our common stock, the general terms and provisions of which are summarized below. This summary does not purport to be complete and is subject to, and is qualified in its entirety by express reference to, the provisions of our articles of incorporation, bylaws and the applicable prospectus supplement.

Authorized Shares

     Under our articles of incorporation, we have the authority to issue 150,000,000 shares of common stock. We have outstanding approximately 91,774,759 shares of our common stock (as of December 17, 2004) and we have reserved for issuance approximately 27,167,072 shares of our common stock (as of December 17, 2004), excluding any shares of common stock that could be issued under the shareholders rights plan.

Dividends

     Subject to any preferential rights of any series of preferred stock, holders of shares of common stock will be entitled to receive dividends on the stock out of assets legally available for distribution when, as and if authorized and declared by our Board of Directors. The payment of dividends on the common stock will be a business decision to be made by our Board of Directors from time to time based upon results of our operations and our financial condition and any other factors as our Board of Directors considers relevant. Payment of dividends on the common stock may be restricted by loan agreements, indentures and other transactions entered into by us from time to time. Any material contractual restrictions on dividend payments will be described in the applicable prospectus supplement.

Voting Rights

     Holders of common stock are entitled to one vote per share on all matters voted on generally by the stockholders, including the election of directors, and, except as otherwise required by law or except as provided with respect to any series of preferred stock, the holders of the shares possess all voting power. Arizona law provides for cumulative voting for the election of directors. As a result, any shareholder may cumulate his or her votes by casting them all for any one director nominee or by distributing them among two or more nominees.

Staggered Terms of Directors

     Our Board of Directors is elected in three classes with staggered three-year terms. We currently have five directors in class I and four directors each in classes II and III. One class of directors is elected each year for a three-year term. Election of directors with staggered terms lessens the effectiveness of cumulative voting rights by reducing the number of directors who are elected in any given year.

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Liquidation Rights

     Subject to any preferential rights of any series of preferred stock, holders of shares of common stock are entitled to share ratably in our assets legally available for distribution to our stockholders in the event of our liquidation, dissolution or winding up.

Absence of Other Rights

     Holders of common stock have no preferential, preemptive, conversion or exchange rights.

Miscellaneous

     All shares of common stock being offered by the applicable prospectus supplement will be fully paid and not liable to further calls or assessment by us.

Transfer Agent and Registrar

     The Bank of New York is the principal transfer agent and registrar for the common stock.

Preferred Stock

     Our Board of Directors has the authority, without any further action by our stockholders, to issue from time to time shares of preferred stock, in one or more series and to fix the designations, preferences, rights, qualifications, limitations and restrictions thereof, including voting rights, dividend rights, dividend rates, conversion rights, terms of redemption, redemption prices, liquidation preferences and the number of shares constituting any series. The issuance of preferred stock with voting rights could have an adverse effect on the voting power of holders of common stock by increasing the number of outstanding shares having voting rights. In addition, if our board of directors authorizes preferred stock with conversion rights, the number of shares of common stock outstanding could potentially be increased up to the authorized amount. The issuance of preferred stock could decrease the amount of earnings and assets available for distribution to holders of common stock. Any such issuance could also have the effect of delaying, deterring or preventing a change in control of us and may adversely affect the rights of holders of our common stock. See also “Description of Preferred Stock” above.

Certain Anti-takeover Effects

     General. Certain provisions of our articles of incorporation, bylaws, and the Arizona Revised Statutes (“ARS”), as well as our shareholder rights plan, may have an anti-takeover effect and may delay or prevent a tender offer or other acquisition transaction that a shareholder might consider to be in his or her best interest, including a transaction that results in a premium over the market price of the common stock. The summary of the provisions of our articles, bylaws, shareholder rights plan, and the ARS set forth below does not purport to be complete and is qualified in its entirety by reference to our articles, bylaws, shareholder rights plan, and the ARS.

     Business Combinations. ARS § 10-2741 through 2743 and Article XII of our bylaws restrict a wide range of transactions (collectively, “business combinations”) between us or, in certain cases, one of our subsidiaries, and an interested shareholder (or any affiliate or associate of the interested shareholder). An “interested shareholder” is, generally, any person who beneficially owns, directly or indirectly, 10% or more of our outstanding voting power or any of our affiliates or associates who at any time within the prior three years was such a beneficial owner. The statute broadly defines “business combinations” to include, among other things and with certain exceptions:

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     The ARS and our bylaws provide that, subject to certain exceptions, we may not engage in a business combination with an interested shareholder (or any affiliate or associate of the interested shareholder) or authorize one of our subsidiaries to do so, for a period of three years after the date on which the interested shareholder first acquired the shares that qualify such person as an interested shareholder (the “share acquisition date”), unless either the business combination or the interested shareholder’s acquisition of shares on the share acquisition date is approved by a committee of our Board of Directors (comprised solely of disinterested directors or other disinterested persons) prior to the interested shareholder’s share acquisition date.

     In addition, after such three-year period, the ARS and our bylaws prohibit us from engaging in any business combination with an interested shareholder (or any affiliate or associate of the interested shareholder), subject to certain exceptions, unless:

     Anti-Greenmail Provisions. ARS § 10-2704 and Article XIII of our bylaws prohibit us from purchasing any shares of our voting stock from any beneficial owner (or group of beneficial owners acting together to acquire, own or vote our shares) of more than 5% of the voting power of our outstanding

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shares at a price per share in excess of the average closing sale price during the 30 trading days preceding the purchase or if the person or persons have commenced a tender offer or announced an intention to seek control of us, during the 30 trading days prior to the commencement of the tender offer or the making of the announcement, unless

     Control Share Acquisition Statute. Through a provision in our bylaws, we have opted out of ARS § 10-2721 through 2727, the Arizona statutory provisions regulating control share acquisitions. As a result, potential acquirors are not subject to the limitations imposed by that statute.

     Shareholder Rights Plan. We have adopted a shareholder rights plan under which one preferred share purchase right is attached to each outstanding share of our common stock. The rights become exercisable and will be separated from the common stock on the Distribution Date, as such term is defined in the plan. Generally, subject to specified exceptions, the Distribution Date will occur on the earlier of:

     Each right entitles the registered holder to purchase from us one one-hundredth of a share of Series A Participating Preferred Stock at an exercise price of $130, subject to adjustment under specified circumstances. However, after any person has become an acquiring person (a “Flip-In Event”), upon exercise of the right, the holder will be entitled to receive common stock valued at twice the exercise price of the right. In other words, a rights holder may purchase common stock at a 50% discount. In some circumstances, the holder will receive cash, property or other securities instead of common stock. Upon the occurrence of a Flip-In Event, any rights owned by an acquiring person, its affiliates and associates and certain of its transferees will become null and void.

     In the event that a person becomes an acquiring person, we are then merged, and the common stock is exchanged or converted in the merger, then each right (other than those formerly held by the acquiring person, which became void) would “flip-over” and be exercisable for a number of shares of common stock of the acquiring company having a market value of two times the exercise price of the right. In other words, a rights holder may purchase the acquiring company’s common stock at a 50% discount.

     After a Flip-In Event but before a “flip-over” event (as described above) occurs and before an acquiring person becomes the owner of 50% or more of the common stock, the Board may cause the rights (either in whole or in part) to be exchanged for shares of common stock (or fractional interests in Series A Preferred Stock, or equivalent securities, of equal value) at a one-to-one exchange ratio. Rights held by the acquiring person, however, which became void upon the Flip-In Event, would not be entitled to participate in such exchange.

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     We may redeem the rights for $0.01 per right at any time prior to the date on which a person becomes an acquiring person. The shareholder rights plan and the rights expire in March 2009, subject to extension.

     For so long as the rights are redeemable, the terms of the rights may be amended or supplemented by the Board of Directors at any time and from time to time without the consent of the holders of the rights. At any time when the rights are not redeemable, the Board of Directors may amend or supplement the terms of the rights, provided that such amendment does not adversely affect the interests of the holders of the rights. In no event may any amendment or supplement be made which changes the redemption price.

     Until a right is exercised, the holder thereof will have no rights as a stockholder, including, without limitation, the right to vote or to receive dividends, except as holder of the common stock to which the right is attached.

     For information on the terms of the Series A Preferred Stock, see the certificate of designation for the Series A Preferred Stock, the form of which is attached as Exhibit A to the Amended and Restated Rights Agreement, dated as of March 26, 1999, filed as an exhibit to our Current Report on Form 8-K dated March 22, 1999, which is incorporated herein by reference.

     Special Meetings of Shareholders. Pursuant to ARS § 10-702, except with respect to certain business combinations, as required by Arizona law, a special meeting of shareholders may be called by a corporation’s Board of Directors or any other person authorized to do so in its articles of incorporation or bylaws. Our bylaws provide that, except as required by law, special meetings of shareholders may only be called by a majority of our Board of Directors, the Chairman of the Board, or the President.

     Election and Removal of Directors. Our Board of Directors is divided into three classes. The directors in each class serve for a three year term, with one class being elected each year by our shareholders. The classification of our Board of Directors generally makes it more difficult for shareholders to effect a change in control because at least two shareholder meetings are required to elect a majority of our Board. Arizona law provides for cumulative voting in the election of directors, which may make it more difficult for shareholders to elect a majority of the Board of Directors.

     Our bylaws provide that any director may be removed with or without cause, but only at a special meeting of shareholders called for that purpose, if the votes cast in favor of such removal exceed the votes cast against such removal. However, if less than the entire Board of Directors is to be removed, no one director may be removed if the votes cast against the director’s removal would be sufficient to elect the director if then cumulatively voted at an election of the class of directors of which the director is a part.

     Shareholder Proposals and Director Nominations. A shareholder can submit shareholder proposals and nominate candidates for election to our Board of Directors if he or she follows the advance notice provisions set forth in our bylaws.

     With respect to shareholder proposals to bring business before the annual meeting, shareholders must submit a written notice to the Secretary of the Company not fewer than 90 nor more than 120 days prior to the first anniversary of the date of our previous year’s annual meeting of shareholders. However, if we have changed the date of the annual meeting by more than 30 days from the date of the previous year’s annual meeting, the written notice must be submitted no earlier than 120 days before the annual meeting and not later than 90 days before the annual meeting or ten days after the day we make public the date of the annual meeting. The written notice must briefly describe the business the shareholder desires to bring before the meeting, the text of the proposal or business, the reasons for conducting such business at the meeting, and any material interest in the proposal of the shareholder and the beneficial owner, if any, on whose behalf the proposal is made.

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     With respect to director nominations, shareholders must submit written notice to the Secretary of the Company at least 180 days prior to the date of the annual meeting. This requirement is also contained in our articles of incorporation. Our bylaws require that the written notice must contain all information relating to the director nominee that is required to be included in a proxy statement pursuant to Regulation 14A under the Securities Exchange Act of 1934, as well as the written consent of the proposed nominee to be named in the proxy statement as a nominee and to serving as a director if elected.

     All written notices delivered pursuant to the advance notice provisions of our bylaws are required to state (i) the name and address as they appear on our books of the sponsoring shareholder and the beneficial owner, if any, on whose behalf the proposal or nomination is made, (ii) the class and number of shares that are owned beneficially and of record by the shareholder and such beneficial owner, (iii) a representation that the shareholder is a holder of record entitled to vote at the meeting and intends to appear in person or by proxy at the meeting to propose such business or nomination, and (iv) whether the shareholder or beneficial owner intends or is part of a group that intends to deliver a proxy statement to holders of at least the number of shares required to adopt the proposal or elect the nominee or otherwise solicit proxies in favor of the proposal or nomination.

     Shareholder proposals and director nominations that are late or that do not include all required information may be rejected. This could prevent shareholders from bringing certain matters before an annual meeting, including proposing the election of non-incumbent directors.

     A shareholder must also comply with all applicable laws in proposing business to be conducted and in nominating directors. The notice provisions of the bylaws do not affect rights of shareholders to request inclusion of proposals in our proxy statement pursuant to Rule 14a-8 of the Securities Exchange Act of 1934.

     Additional Authorized Shares of Capital Stock. The authorized but unissued shares of common stock and preferred stock available for issuance under our articles of incorporation could be issued at such times, under such circumstances, and with such terms and conditions as to impede an acquisition transaction.

     Amendment to Articles of Incorporation and Bylaws. ARS § 10-1001 through 1003 generally provide that both the Board of Directors and the shareholders must approve amendments to an Arizona corporation’s articles of incorporation, except that the Board of Directors may adopt specified ministerial amendments without shareholder approval. Unless the articles of incorporation, Arizona law or the Board of Directors would require a greater vote or unless the articles or Arizona law would require a different quorum, the vote required by each voting group allowed or required to vote on the amendment would be:

     Our articles of incorporation require the approval of at least two-thirds of the total voting power of all outstanding shares of our voting stock to amend the provisions in Article Third relating to serial preferred stock, Article Fifth relating to the election of our directors, including number, classification, term, and nomination procedure, and Article Tenth relating to this voting requirement.

     ARS § 10-1020 provides that the Board of Directors may amend the corporation’s bylaws unless either: (i) the articles or applicable law reserves this power exclusively to shareholders in whole or in part or (ii) the shareholders in amending or repealing a particular bylaw provide expressly that the Board may

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not amend or repeal that bylaw. An Arizona corporation’s shareholders may amend the corporation’s bylaws even though they may also be amended by the Board of Directors. Our bylaws may not be amended or repealed without the vote of a majority of the Board of Directors or the affirmative vote of a majority of votes cast on the matter at a meeting of shareholders.

DESCRIPTION OF THE PURCHASE CONTRACTS

     We may issue, from time to time, purchase contracts, including contracts obligating holders to purchase from us and us to sell to the holders, a specified principal amount of debt securities or a specified number of shares of common stock or preferred stock or any of the other securities that we may sell under this prospectus (or a range of principal amount or number of shares pursuant to a predetermined formula) at a future date or dates. The consideration payable upon settlement of the purchase contracts may be fixed at the time the purchase contracts are issued or may be determined by a specific reference to a formula set forth in the purchase contracts. The purchase contracts may be issued separately or as part of units consisting of a purchase contract and other securities or obligations issued by us or third parties, including United States treasury securities, securing the holders’ obligations to purchase the relevant securities under the purchase contracts. The purchase contracts may require us to make periodic payments to the holders of the purchase contracts or units or vice versa, and the payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations under the purchase contracts in a specified manner and in certain circumstances we may deliver newly issued prepaid purchase contracts, often known as prepaid securities, upon release to a holder of any collateral securing such holder’s obligations under the original purchase contract.

     The applicable prospectus supplement will describe the terms of any purchase contracts or purchase units and, if applicable, such other securities or obligations. The description in the prospectus supplement will not necessarily be complete and will be qualified in its entirety by reference to the purchase contracts, and, if applicable, collateral arrangements and depositary arrangements, relating to the purchase contracts.

DESCRIPTION OF UNITS

     We may, from time to time, issue units comprised of one or more of the other securities that may be offered under this prospectus, in any combination. Each unit may be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately at any time, or at any time before a specified date.

     Any applicable prospectus supplement will describe:

PLAN OF DISTRIBUTION

     We may sell the securities to one or more underwriters for public offering and sale by them or may sell the securities to investors through agents or dealers. Any underwriter or agent involved in the

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offer and sale of the securities will be named in the applicable prospectus supplement. We also reserve the right to sell securities directly to investors on our own behalf in those jurisdictions where we are authorized to do so.

     Underwriters may offer and sell the securities at a fixed price or prices, which may be changed, or from time to time at market prices prevailing at the time of sale, at prices related to prevailing market prices or at negotiated prices. We also may, from time to time, authorize underwriters acting as our agents to offer and sell the securities upon the terms and conditions set forth in any prospectus supplement. In connection with the sale of the securities, underwriters may be deemed to have received compensation from us in the form of underwriting discounts or commissions and may also receive commissions from purchasers of the securities for whom they may act as agent.

     If a dealer is utilized in the sale of the securities in respect of which this prospectus is delivered, we may sell the securities to the dealer, as principal. The dealer may then resell the securities to the public at varying prices to be determined by the dealer at the time of resale.

     Any underwriting compensation paid by us to underwriters or agents in connection with the offering of the securities, and any discounts, concessions or commissions allowed by underwriters to participating dealers, will be set forth in an applicable prospectus supplement. Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters under the Securities Act, and any discounts and commissions received by them and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. Underwriters, dealers and agents may be entitled under agreements with us to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act, and to reimbursement by us for certain expenses. Unless otherwise indicated in the prospectus supplement, any agreement we enter into with the underwriters will provide that the obligations of any underwriters to purchase the securities will be subject to certain conditions precedent and the underwriter or underwriters are obligated to purchase all of the securities offered in the prospectus supplement if any are purchased.

     In connection with underwritten offerings of securities, underwriters may over-allot or effect transactions that stabilize, maintain or otherwise affect the market price of the offered securities at levels above those that might otherwise prevail in the open market, including by entering stabilizing bids, effecting syndicate covering transactions or imposing penalty bids, each of which is described below.

     These transactions may be effected on the New York Stock Exchange, in the over-the-counter market or otherwise. Underwriters are not required to engage in any of these activities, or to continue the activities if commenced.

     The securities may also be offered and sold, if so indicated in the prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms (“remarketing firms”), acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its

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agreement, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters in connection with the securities remarketed by them. Remarketing firms may be entitled under agreements which may be entered into with us to indemnification by us against certain liabilities, including liabilities under the Securities Act.

     The securities may or may not be listed on a national securities exchange or a foreign securities exchange. No assurances can be given that there will be a market for any of the securities.

     One or more of the underwriters, and/or one or more of their respective affiliates, may be a lender under our credit agreements or those of our affiliates and may provide other commercial banking, investment banking and other services to us and/or our affiliates in the ordinary course of business.

     We may enter into derivative transactions with third parties, or sell securities not covered by this prospectus to third parties in privately negotiated transactions. If the applicable prospectus supplement indicates, in connection with those securities, the third parties may sell securities covered by this prospectus and the applicable prospectus supplement, including in short sales transactions. If so, the third party may use securities pledged by us or borrowed from us or others to settle those sales or to close out any related open borrowings of stock, and may use securities received from us in settlement of those derivatives to close out any related open borrowings of stock. The third party in such sale transactions will be an underwriter and will be identified in the applicable prospectus supplement.

EXPERTS

     The financial statements and the related financial statement schedule incorporated in this prospectus by reference from Pinnacle West Capital Corporation’s Current Report on Form 8-K filed December 20, 2004, have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report (which report expresses an unqualified opinion and includes explanatory paragraphs relating to the change in 2003 in the method of accounting for non-trading derivatives, to the change in 2002 in the method of accounting for trading activities and to the change in 2001 in the method of accounting for derivatives and hedging activities), which is incorporated by reference herein, and have been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

LEGAL OPINIONS

     Snell & Wilmer L.L.P., One Arizona Center, Phoenix, Arizona 85004, will opine on the validity of the offered securities. We currently anticipate that Pillsbury Winthrop LLP, 1540 Broadway, New York, New York 10036, will opine on the validity of the offered securities for any underwriters of securities. Snell & Wilmer L.L.P. may rely as to all matters of New York law upon the opinion of Pillsbury Winthrop LLP. Pillsbury Winthrop LLP may rely as to all matters of Arizona law upon the opinion of Snell & Wilmer L.L.P.

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$500,000,000

PINNACLE WEST CAPITAL CORPORATION

DEBT SECURITIES

PREFERRED STOCK

COMMON STOCK

PURCHASE CONTRACTS

UNITS

PNW

PART II
INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses Of Issuance And Distribution.

Item 15. Indemnification Of Directors And Officers.

     The Arizona Business Corporation Act (the “ABCA”) permits extensive indemnification of present and former directors, officers, employees or agents of an Arizona corporation, whether or not authority for such indemnification is contained in the indemnifying corporation’s articles of incorporation or bylaws. Specific authority for indemnification of present and former directors and officers to the fullest extent permitted by applicable law is contained in Article VII of our bylaws. Such indemnification is mandatory.

     Under the ABCA, in order for a corporation to indemnify a director or officer, a majority of the corporation’s disinterested directors, special legal counsel, or the shareholders must find that the conduct of the individual to be indemnified was in good faith and that the individual reasonably believed that the conduct was in the corporation’s best interests (in the case of conduct in an “official capacity” with the corporation) or that the conduct was at least not opposed to the corporation’s best interests (in all other cases). In the case of any criminal proceeding, the finding must be to the effect that the individual had no reasonable cause to believe the conduct was unlawful. Indemnification is permitted with respect to expenses, judgments, fines, and amounts paid in settlement by such individuals. However, a corporation cannot indemnify a director in the cases noted in clause (ii) of the second sentence of the following paragraph. Broader indemnification is allowed, with certain limitations, for a director as provided in a corporation’s articles of incorporation and for an officer who is not also a director or where the basis on which the officer was made a party to the proceeding is an act or omission solely as an officer, as provided in the articles of incorporation, bylaws, a resolution of the board of directors or a contract.

     Indemnification under the ABCA is permissive, except in the event of a successful defense, in which case a director or officer must be indemnified against reasonable expenses, including attorneys’ fees, incurred in connection with the proceeding. In addition, the ABCA requires Arizona corporations to indemnify any “outside director” (a director who is not an officer, employee or holder of more than five percent of any class of the corporation’s stock or the stock of any affiliate of the corporation) against liability unless (i) the corporation’s articles of incorporation limit such indemnification, (ii) the director is adjudged liable in a proceeding by or in the right of the corporation or in any other proceeding charging improper financial benefit to the director, whether or not involving action in the director’s official capacity, in which the director was adjudged liable on the basis that the financial benefit was improperly received by the director, or (iii) a court determines, before payment to the outside director, that the director failed to meet the standards of conduct described in the preceding paragraph. With certain limitations, a court may also order that an individual be indemnified if the court finds that the individual is fairly and reasonably entitled to indemnification in light of all of the relevant circumstances, whether or not the

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individual has met the standards of conduct in this and the preceding paragraph or was adjudged liable as described above.

     In connection with the offering made by the prospectus which is a part of this registration statement, as it may be amended or supplemented, the underwriters of the securities, pursuant to the relevant underwriting agreement, will severally agree to indemnify and hold harmless us, each of our directors, each of our officers who has signed this registration statement, and each person, if any, who controls us within the meaning of the Securities Act of 1933, as amended (the “Act”), against certain losses, claims, damages, or liabilities, including liabilities under the Act, that arise out of or are based upon written information furnished by such underwriters to us for use in this registration statement or in such prospectus.

     Insurance is maintained on a regular basis (and not specifically in connection with this offering) against liabilities arising on the part of directors and officers out of their performance in such capacities or arising on our part out of the foregoing indemnification provisions, subject to certain exclusions and to the policy limits.

     For information regarding our undertaking to submit to adjudication the issue of indemnification for violation of the securities laws, see Item 17 below.

Item 16. Exhibits.

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     In addition to those Exhibits shown above, the Company hereby incorporates the following Exhibits pursuant to Rule 411 of Regulation C promulgated under the Act by reference to the filings set forth below:

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Item 17. Undertakings.

     The undersigned registrant hereby undertakes:

     (1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

     (i) to include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;

     (ii) to reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement; notwithstanding the foregoing, any increase or decrease in the volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

     (iii) to include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement; provided however, that paragraphs (1)(i) and (1)(ii) do not apply if the registration statement is on Form S-3 or Form S-8 and the information required to be included in a post-effective amendment by those paragraphs is contained in periodic reports filed with or furnished to the Commission by the registrant pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement.

     (2) That, for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

     (3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.

     (4) That, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant’s annual report pursuant to section 13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing of an employee benefit plan’s annual report pursuant to Section 15(d) of the Securities Exchange Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

     (5) That, insofar as indemnification for liabilities arising under the Securities Act of 1933 may be permitted to directors, officers, and controlling persons of the registrant pursuant to the provisions referred to in Item 15 of this Registration Statement, or otherwise, the registrant has been advised that, in the opinion of the Securities and Exchange Commission, such indemnification is against public policy as expressed in the Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer, or controlling person of the registrant in the successful defense of any action, suit, or proceeding) is asserted by such director, officer, or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question of whether such indemnification by it is against public policy as expressed in the Act and will be governed by the final adjudication of such issue.

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SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing this registration statement on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Phoenix, State of Arizona on the 21st day of December, 2004.

     Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated. Each person whose signature appears below hereby authorizes Donald E. Brandt, Barbara M. Gomez and Nancy C. Loftin, and each of them, as attorneys-in-fact, to sign in his or her name and behalf, individually and in each capacity designated below, and to file any amendments, including post-effective amendments, to this registration statement.

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For a description of the Exhibits incorporated in this filing by reference, see Item 16.