We have investments in debt and equity securities held in nuclear decommissioning trusts and other special use funds. Investments in debt securities are classified as available-for-sale securities. We record both debt and equity security investments at their fair value on our Condensed Consolidated Balance Sheets. See Note 13 for a discussion of how fair value is determined and the classification of the investments within the fair value hierarchy. The investments in each trust or account are restricted for use and are intended to fund specified costs and activities as further described for each fund below.

APS established external decommissioning trusts in accordance with NRC regulations to fund the future costs APS expects to incur to decommission Palo Verde. Third-party investment managers are authorized to buy and sell securities per stated investment guidelines. The trust funds are invested in fixed income securities and equity securities. Earnings and proceeds from sales and maturities of securities are reinvested in the trusts. Because of the ability of APS to recover decommissioning costs in rates, and in accordance with the regulatory treatment, APS has deferred realized and unrealized gains and losses (including credit losses) in other regulatory liabilities.

APS has investments restricted for the future coal mine reclamation funding related to Four Corners. This escrow account is primarily invested in fixed income securities. Earnings and proceeds

from sales of securities are reinvested in the escrow account. Because of the ability of APS to recover coal reclamation costs in rates, and in accordance with the regulatory treatment, APS has deferred realized and unrealized gains and losses (including credit losses) in other regulatory liabilities. Activities relating to APS coal mine reclamation escrow account investments are included within the other special use funds in the table below.

APS has investments restricted for paying active union employee medical costs. These investments may be used to pay active union employee medical costs incurred in the current and future periods. In 2024, APS was reimbursed $14 million for prior year active union employee medical claims from the active union employee medical account. The account is invested primarily in fixed income securities. In accordance with the ratemaking treatment, APS has deferred the unrealized gains and losses (including credit losses) in other regulatory assets and liabilities. Activities relating to active union employee medical account investments are included within the other special use funds in the table below.

Pinnacle West has investments in the Captive that may be used to pay insurance losses in the event of certain insured loss events. The Captive may hold investment assets in cash, cash equivalents, and equity and fixed income instruments. These investments are restricted for insured loss events.

Pinnacle West Consolidated investment holdings reflected in the tables below primarily relate to APS, with the exception of the Captive’s investments included within other special use funds.

The following tables present the unrealized gains and losses based on the original cost of the investment and summarize the fair value of the nuclear decommissioning trusts and other special use fund assets (dollars in thousands):


	March 31, 2025
	Fair Value							Total Unrealized Gains		Total Unrealized Losses
Investment Type:	Nuclear Decommissioning Trusts		Other Special Use Funds		Total
Equity securities	$	416,753	$	37,234	$	453,987		$	341,566	$	(325)
Available for sale-fixed income securities	866,658		376,137		1,242,795		(a)	13,416		(22,318)
Other	2,690		2,030		4,720		(b)	—		—
Total	$	1,286,101	$	415,401	$	1,701,502	(c)	$	354,982	$	(22,643)

(c)All amounts pertain to APS, with the exception of $35.1 million of other special use fund investments in equity securities relating to the Captive.


	December 31, 2024
	Fair Value							Total Unrealized Gains		Total Unrealized Losses
Investment Type:	Nuclear Decommissioning Trusts		Other Special Use Funds		Total
Equity securities	$	435,470	$	24,962	$	460,432		$	359,127	$	(176)
Available for sale-fixed income securities	844,040		355,544		1,199,584		(a)	7,717		(31,960)
Other	3,335		27,851		31,186		(b)	—		—
Total	$	1,282,845	$	408,357	$	1,691,202	(c)	$	366,844	$	(32,136)

(c)All amounts pertain to APS, with the exception of $34.2 million of other special use fund investments in equity securities relating to the Captive.

The following table sets forth realized gains and losses relating to the sale and maturity of available-for-sale debt securities and equity securities, and the proceeds from the sale and maturity of these investment securities (dollars in thousands):


	Three Months Ended March 31,
	Nuclear Decommissioning Trusts		Other Special Use Funds			Total
2025
Realized gains	$	1,658	$	—		$	1,658
Realized losses	$	(2,761)	$	—		$	(2,761)
Proceeds from the sale of securities (a)	$	416,601	$	69,213	(b)	$	485,814
2024
Realized gains	$	54,492	$	80		$	54,572
Realized losses	$	(2,815)	$	—		$	(2,815)
Proceeds from the sale of securities (a)	$	377,822	$	66,048		$	443,870

(a) Proceeds are reinvested in the nuclear decommissioning trusts and other special use funds, excluding investment fees and amounts reimbursed to the Company for active union employee medical claims from the active union employee medical account.

(b) All amounts pertain to APS, with the exception of $25.3 million of other special use fund proceeds from the sale of securities relating to the Captive.


	Nuclear Decommissioning Trusts		Coal Reclamation Escrow Account		Active Union Employee Medical Account		Captive Insurance Cell (a)	Total
Less than one year	$	32,422	$	90,167	$	39,464	25,149	$	187,202
1 year – 5 years	292,409		48,289		157,055		—	497,753
5 years – 10 years	137,989		—		16,013		—	154,002
Greater than 10 years	403,838		—		—		—	403,838
Total	$	866,658	$	138,456	$	212,532	25,149	$	1,242,795

(a)All amounts pertain to APS, with the exception of $25.1 million of other special use fund investments in fixed income securities relating to the Captive.