Accumulated Other Comprehensive (Loss) Income (Tables)

9 Months Ended

Sep. 30, 2025

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Summary of Changes in Accumulated Other Comprehensive (Loss) Income by Component

The following table details the activity of the three components that comprise Accumulated other comprehensive (loss) income for Alcoa Corporation’s shareholders and Noncontrolling interest:

	Alcoa Corporation						Noncontrolling interest
	Third quarter ended September 30,						Third quarter ended September 30,
	2025			2024			2025		2024
Pension and other postretirement benefits (L)
Balance at beginning of period	$	5		$	22		$	—	$	(9	)
Other comprehensive income (loss):
Unrecognized net actuarial gain/loss and    prior service cost/benefit		1			(5	)		—		(2	)
Tax benefit(2)		1			1			—		—
Total Other comprehensive income (loss)    before reclassifications, net of tax		2			(4	)		—		(2	)
Amortization of net actuarial gain/loss and    prior service cost/benefit(1)		5			5			—		—
Total amount reclassified from Accumulated    other comprehensive loss, net of tax(7)		5			5			—		—
Total Other comprehensive income (loss)		7			1			—		(2	)
Acquisition of noncontrolling interest (C)		—			(11	)		—		11
Balance at end of period	$	12		$	12		$	—	$	—
Foreign currency translation
Balance at beginning of period	$	(3,833	)	$	(2,775	)	$	10	$	(1,053	)
Other comprehensive income (loss)		87			144			—		(35	)
Acquisition of noncontrolling interest (C)		—			(1,088	)		—		1,088
Balance at end of period	$	(3,746	)	$	(3,719	)	$	10	$	—
Cash flow hedges (M)
Balance at beginning of period	$	(936	)	$	(984	)	$	—	$	(1	)
Other comprehensive (loss) income:
Net change from periodic revaluations		(207	)		(143	)		—		—
Tax benefit(2)		34			33			—		—
Total Other comprehensive loss    before reclassifications, net of tax		(173	)		(110	)		—		—
Net amount reclassified to earnings:
Aluminum contracts(3)		86			73			—		—
Financial contracts(4)		4			—			—		—
Interest rate contracts(5)		—			—			—		1
Foreign exchange contracts(6)		—			1			—		—
Sub-total		90			74			—		1
Tax expense(2)		(17	)		(15	)		—		—
Total amount reclassified from Accumulated    other comprehensive loss, net of tax(7)		73			59			—		1
Total Other comprehensive (loss) income		(100	)		(51	)		—		1
Balance at end of period	$	(1,036	)	$	(1,035	)	$	—	$	—
Total Accumulated other comprehensive (loss) income	$	(4,770	)	$	(4,742	)	$	10	$	—

	Alcoa Corporation						Noncontrolling interest
	Nine months ended September 30,						Nine months ended September 30,
	2025			2024			2025		2024
Pension and other postretirement benefits (L)
Balance at beginning of period	$	(11	)	$	—		$	—	$	(15	)
Other comprehensive income:
Unrecognized net actuarial gain/loss and    prior service cost/benefit		1			9			—		5
Tax benefit (expense)(2)		3			(2	)		—		(2	)
Total Other comprehensive income    before reclassifications, net of tax		4			7			—		3
Amortization of net actuarial gain/loss and    prior service cost/benefit(1)		19			16			—		1
Total amount reclassified from Accumulated    other comprehensive loss, net of tax(7)		19			16			—		1
Total Other comprehensive income		23			23			—		4
Acquisition of noncontrolling interest (C)		—			(11	)		—		11
Balance at end of period	$	12		$	12		$	—	$	—
Foreign currency translation
Balance at beginning of period	$	(4,194	)	$	(2,593	)	$	—	$	(983	)
Other comprehensive income (loss)		479			(38	)		10		(105	)
Acquisition of noncontrolling interest (C)		—			(1,088	)		—		1,088
Joint venture formation (C)		(31	)		—			—		—
Balance at end of period	$	(3,746	)	$	(3,719	)	$	10	$	—
Cash flow hedges (M)
Balance at beginning of period	$	(905	)	$	(1,052	)	$	—	$	—
Other comprehensive (loss) income:
Net change from periodic revaluations		(420	)		(179	)		—		—
Tax benefit(2)		75			33			—		—
Total Other comprehensive loss    before reclassifications, net of tax		(345	)		(146	)		—		—
Net amount reclassified to earnings:
Aluminum contracts(3)		257			205			—		—
Financial contracts(4)		6			—			—		—
Interest rate contracts(5)		—			(1	)		—		—
Foreign exchange contracts(6)		2			(3	)		—		—
Sub-total		265			201			—		—
Tax expense(2)		(51	)		(38	)		—		—
Total amount reclassified from Accumulated    other comprehensive loss, net of tax(7)		214			163			—		—
Total Other comprehensive (loss) income		(131	)		17			—		—
Balance at end of period	$	(1,036	)	$	(1,035	)	$	—	$	—
Total Accumulated other comprehensive (loss) income	$	(4,770	)	$	(4,742	)	$	10	$	—

(1)These amounts were included in the computation of net periodic benefit cost for pension and other postretirement benefits (see Note L).

(2)These amounts were reported in (Benefit from) provision for income taxes on the accompanying Statement of Consolidated Operations.

(3)These amounts were reported in Sales on the accompanying Statement of Consolidated Operations.

(4)These amounts were reported in Cost of goods sold on the accompanying Statement of Consolidated Operations.

(5)These amounts were reported in Other (income) expenses, net on the accompanying Statement of Consolidated Operations.

(6)For the third quarter and nine-month period of 2025, these amounts were reported in Sales (both periods) on the accompanying Statement of Consolidated Operations. For the third quarter and nine-month period of 2024, $2 and $(2) were reported in Sales, respectively, and $(1) was reported in Cost of goods sold (both periods) on the accompanying Statement of Consolidated Operations.

(7)A positive amount indicates a corresponding charge to earnings and a negative amount indicates a corresponding benefit to earnings.