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USD ($)

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   &lt;div style="font-family: 'Times New Roman',Times,serif; margin-left: 0in; "&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;6. Income Taxes&lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%"&gt;The $68&amp;#160;million income tax receivable on the Condensed Consolidated Balance Sheets represents
   the anticipated refunds related to an APS tax accounting method change approved by the IRS in the
   third quarter of 2009. This amount is classified as long-term, as cash refunds are not expected to
   be received in the next twelve months.
   &lt;/div&gt;
   &lt;!-- Folio --&gt;
   &lt;!-- /Folio --&gt;
   &lt;/div&gt;
   &lt;!-- PAGEBREAK --&gt;
   &lt;div style="font-family: 'Times New Roman',Times,serif; margin-left: 0in; "&gt;
   &lt;div align="center" style="font-size: 10pt; margin-top: 0pt"&gt;
   &lt;b&gt;
   &lt;/b&gt;
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%"&gt;On February&amp;#160;17, 2011, Arizona enacted legislation (H.B. 2001) that included a four year
   phase-in of corporate income tax rate reductions beginning in 2014. As a result of these tax rate
   reductions, Pinnacle West has revised the tax rate applicable to reversing temporary items in
   Arizona. In accordance with accounting for regulated companies, the benefit of this rate reduction
   is substantially offset by a regulatory liability. In the first quarter of 2011, Pinnacle West
   increased regulatory liabilities by a total of $53&amp;#160;million, with a corresponding decrease in
   accumulated deferred income tax liabilities to reflect the impact of this change in tax law.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%"&gt;As of the balance sheet date, the tax year ended December&amp;#160;31, 2008 and all subsequent tax
   years remain subject to examination by the IRS. With few exceptions, we are no longer subject to
   state income tax examinations by tax authorities for years before 2006. We do not anticipate that
   there will be any significant increases or decreases in our unrecognized tax benefits within the
   next twelve months.
   &lt;/div&gt;
   &lt;/div&gt;
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 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 08
 -Paragraph h
 -Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 109
 -Paragraph 136, 172

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 109
 -Paragraph 43, 44, 45, 46, 47, 48, 49

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