Business Segments (Tables)

3 Months Ended

Mar. 31, 2026

Segment Reporting [Abstract]

Schedule of Reportable Segment’s Revenues, Significant Expenses, Net Income, and Assets

The following table reconciles our reportable segment’s revenues, significant expenses, and net income (loss) to the Pinnacle West consolidated amounts (dollars in millions):

	Three Months Ended March 31,
	2026						2025
	Regulated Electricity Segment		Other		Pinnacle West Consolidated		Regulated Electricity Segment		Other		Pinnacle West Consolidated
Operating revenues	$	1,150	$	—	$	1,150	$	1,032	$	—	$	1,032
Fuel and purchased power	(437)		—		(437)		(380)		—		(380)
Operations and maintenance	(273)		(4)		(277)		(297)		(3)		(300)
Depreciation and amortization	(240)		—		(240)		(235)		—		(235)
Taxes other than income taxes	(62)		—		(62)		(59)		—		(59)
Allowance for equity funds used during construction	15		—		15		13		—		13
Pension and other postretirement non-service credits, net	4		—		4		3		—		3
Other income and (expense), net	(3)		2		(1)		3		11		14
Interest charges, net of allowance for borrowed funds used during construction	(92)		(24)		(116)		(79)		(16)		(95)
Income (taxes) benefit	(8)		7		(1)		3		3		6
Less: Net income attributable to noncontrolling interests	(2)		—		(2)		(4)		—		(4)
Net Income (Loss) Attributable to Common Shareholders	$	52	$	(19)	$	33	$	—	$	(5)	$	(5)

The following table reconciles our reportable segment’s assets to the Pinnacle West consolidated amount (dollars in millions):

	March 31, 2026						December 31, 2025
	Regulated Electricity Segment		Other		Pinnacle West Consolidated		Regulated Electricity Segment		Other		Pinnacle West Consolidated
Total Assets	$	30,524	$	167	$	30,691	$	29,886	$	146	$	30,032