Employee Benefit Plans

3 Months Ended

Mar. 31, 2024

Retirement Benefits [Abstract]

Employee Benefit Plans

EMPLOYEE BENEFIT PLANS

DEFINED BENEFIT RETIREMENT PLANS

Duke Energy and certain subsidiaries maintain, and the Subsidiary Registrants participate in, qualified and non-qualified, non-contributory defined benefit retirement plans. Duke Energy's policy is to fund amounts on an actuarial basis to provide assets sufficient to meet benefit payments to be paid to plan participants.

QUALIFIED PENSION PLANS

The following tables include the components of net periodic pension costs for qualified pension plans.

	Three Months Ended March 31, 2024
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana		Piedmont
Service cost	$	28	$	9	$	8	$	5	$	3	$	1	$	2	$	1
Interest cost on projected benefit obligation	82		20		26		12		14		4		6		2
Expected return on plan assets	(154)		(41)		(54)		(25)		(29)		(6)		(10)		(5)
Amortization of actuarial loss	8		2		2		1		1		—		1		1
Amortization of prior service credit	(3)		—		—		—		—		—		—		(2)
Amortization of settlement charges	5		2		1		1		—		—		—		1
Net periodic pension costs	$	(34)	$	(8)	$	(17)	$	(6)	$	(11)	$	(1)	$	(1)	$	(2)

	Three Months Ended March 31, 2023
			Duke				Duke		Duke		Duke		Duke
	Duke		Energy		Progress		Energy		Energy		Energy		Energy
(in millions)	Energy		Carolinas		Energy		Progress		Florida		Ohio		Indiana		Piedmont
Service cost	$	30	$	10	$	9	$	5	$	3	$	1	$	1	$	1
Interest cost on projected benefit obligation	86		21		27		12		14		4		7		2
Expected return on plan assets	(147)		(40)		(50)		(23)		(26)		(6)		(10)		(5)
Amortization of actuarial loss	2		—		1		—		1		—		1		—
Amortization of prior service credit	(3)		—		—		—		—		—		—		(2)
Amortization of settlement charges	5		2		1		1		—		—		—		1
Net periodic pension costs	$	(27)	$	(7)	$	(12)	$	(5)	$	(8)	$	(1)	$	(1)	$	(3)

NON-QUALIFIED PENSION PLANS

Net periodic pension costs for non-qualified pension plans were not material for the three months ended March 31, 2024, and 2023.

OTHER POST-RETIREMENT BENEFIT PLANS

Net periodic costs for OPEB plans were not material for the three months ended March 31, 2024, and 2023.