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                                November 6, 2003

Pinnacle West Capital Corporation
400 North 5th Street
Phoenix, Arizona  85004

Ladies and Gentlemen:

      Reference is made to (a) your proposed offering of up to $600,000,000 of
your securities, as contemplated by the registration statement (the
"Registration Statement") on Form S-3, No. 333-101457 filed by you with the
Securities and Exchange Commission (the "Commission") under the Securities Act
of 1933, as amended (the "Act"), on November 25, 2002, and declared effective by
the Commission on December 5, 2002, which securities include debt securities,
preferred stock, common stock, purchase contracts, units or any combination
thereof; and (b) your issuance and sale of $165,000,000 aggregate principal
amount of Floating Rate Senior Notes due 2005 (the "Notes"), pursuant to the
Underwriting Agreement dated November 6, 2003 (the "Underwriting Agreement")
between you and the underwriters named therein and the Indenture dated as of
December 1, 2000, as amended and supplemented to the date hereof and as further
amended and supplemented by the Second Supplemental Indenture thereto dated as
of November 1, 2003, in substantially the form filed by you as Exhibit 4.20 to
your Form 8-K Report dated November 6, 2003 (the "Indenture").

      We have examined the definitive prospectus, dated December 5, 2002, and
the prospectus supplement, dated November 6, 2003 (the prospectus and prospectus
supplement, and all material incorporated therein by reference being hereinafter
referred to as the "Prospectus"), relating to the Notes. We have also examined
originals or copies, certified or otherwise identified to our satisfaction, of
such corporate records, agreements, and other instruments, certificates, orders,
opinions, correspondence with public officials, certificates provided by your
officers and representatives, and other documents as we have deemed necessary or
advisable for the purposes of rendering the opinions set forth herein.

      Based on the foregoing, it is our opinion that upon the issuance and
delivery of the Notes in accordance with the Underwriting Agreement and the
Indenture, and receipt by you of the consideration set forth in the Prospectus,
the Notes will be validly issued and will constitute your legal, valid, and
binding obligations except as the same may be limited by (a) general principles
of equity or by bankruptcy, insolvency, reorganization, arrangement, moratorium,
or other laws or equitable principles relating to or affecting the enforcement
of creditors' rights generally, and (b) the qualification that certain waivers,
procedures, remedies, and other provisions of the Notes may be unenforceable
under or limited by the law of the State of
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Pinnacle West Capital Corporation
November 6, 2003
Page 2


Arizona; however, such law does not in our opinion substantially prevent the
practical realization of the benefits thereof.

      Consent is hereby given to the use of this opinion as part of the
Registration Statement, and to the use of our name wherever it appears in said
Registration Statement and the related Prospectus.


                                     Very truly yours,


                                     Snell & Wilmer L.L.P.

