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Retirement Benefits | 9 Months Ended
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Sep. 30, 2025
Defined Benefit Plan Disclosure [Line Items] |
Retirement Benefits | Retirement Benefits CMS Energy and Consumers provide pension, OPEB, and other retirement benefits to eligible employees under a number of different plans. Costs: Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefit plans:
In Millions
| DB Pension Plans |  | OPEB Plan
| Three Months Ended |  | Nine Months Ended |  | Three Months Ended |  | Nine Months Ended
September 30 | 2025 | 2024 |  | 2025 | 2024 |  |  | 2025 | 2024 |  | 2025 | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 6 |  |  | $ | 7 |  |  |  | $ | 19 |  |  | $ | 21 |  |  |  |  |  | $ | 2 |  |  | $ | 2 |  |  |  | $ | 6 |  |  | $ | 8 |  |  |
Interest cost |  | 27 |  |  | 26 |  |  |  | 81 |  |  | 78 |  |  |  |  |  | 10 |  |  | 10 |  |  |  | 32 |  |  | 32 |  |  |
Expected return on plan assets |  | (57) |  |  | (58) |  |  |  | (171) |  |  | (176) |  |  |  |  |  | (27) |  |  | (28) |  |  |  | (83) |  |  | (86) |  |  |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 9 |  |  |  |  |  | — |  |  | 1 |  |  |  | 2 |  |  | 3 |  |  |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  |  | 3 |  |  | 3 |  |  |  |  |  | (8) |  |  | (7) |  |  |  | (25) |  |  | (23) |  |  |
Settlement loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 8 |  |  |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  |
Net periodic credit |  | $ | (17) |  |  | $ | (18) |  |  |  | $ | (52) |  |  | $ | (57) |  |  |  |  |  | $ | (23) |  |  | $ | (22) |  |  |  | $ | (68) |  |  | $ | (66) |  |  |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 6 |  |  | $ | 7 |  |  |  | $ | 18 |  |  | $ | 20 |  |  |  |  |  | $ | 2 |  |  | $ | 2 |  |  |  | $ | 6 |  |  | $ | 8 |  |  |
Interest cost |  | 26 |  |  | 25 |  |  |  | 77 |  |  | 74 |  |  |  |  |  | 11 |  |  | 11 |  |  |  | 32 |  |  | 31 |  |  |
Expected return on plan assets |  | (54) |  |  | (56) |  |  |  | (162) |  |  | (166) |  |  |  |  |  | (26) |  |  | (26) |  |  |  | (78) |  |  | (80) |  |  |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 2 |  |  | 3 |  |  |  | 7 |  |  | 8 |  |  |  |  |  | — |  |  | 1 |  |  |  | 2 |  |  | 3 |  |  |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  |  | 3 |  |  | 3 |  |  |  |  |  | (8) |  |  | (8) |  |  |  | (25) |  |  | (23) |  |  |
Settlement loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 8 |  |  |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  |
Net periodic credit |  | $ | (16) |  |  | $ | (17) |  |  |  | $ | (49) |  |  | $ | (53) |  |  |  |  |  | $ | (21) |  |  | $ | (20) |  |  |  | $ | (63) |  |  | $ | (61) |  |  |
In Consumers’ electric and gas rate cases, the MPSC approved a mechanism allowing Consumers to defer for future recovery or refund pension and OPEB expenses above or below the amounts used to set existing rates. Amounts deferred will be collected from or refunded to customers over ten years. At September 30, 2025, CMS Energy, including Consumers, had deferred $1 million of pension costs and $7 million of OPEB credits under this mechanism related to 2025 expense. At September 30, 2024, CMS Energy, including Consumers, had deferred $12 million of pension credits and $8 million of OPEB credits under this mechanism related to 2024 expense.
Consumers Energy Company |
Defined Benefit Plan Disclosure [Line Items] |
Retirement Benefits | Retirement Benefits CMS Energy and Consumers provide pension, OPEB, and other retirement benefits to eligible employees under a number of different plans. Costs: Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefit plans:
In Millions
| DB Pension Plans |  | OPEB Plan
| Three Months Ended |  | Nine Months Ended |  | Three Months Ended |  | Nine Months Ended
September 30 | 2025 | 2024 |  | 2025 | 2024 |  |  | 2025 | 2024 |  | 2025 | 2024 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 6 |  |  | $ | 7 |  |  |  | $ | 19 |  |  | $ | 21 |  |  |  |  |  | $ | 2 |  |  | $ | 2 |  |  |  | $ | 6 |  |  | $ | 8 |  |  |
Interest cost |  | 27 |  |  | 26 |  |  |  | 81 |  |  | 78 |  |  |  |  |  | 10 |  |  | 10 |  |  |  | 32 |  |  | 32 |  |  |
Expected return on plan assets |  | (57) |  |  | (58) |  |  |  | (171) |  |  | (176) |  |  |  |  |  | (27) |  |  | (28) |  |  |  | (83) |  |  | (86) |  |  |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 9 |  |  |  |  |  | — |  |  | 1 |  |  |  | 2 |  |  | 3 |  |  |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  |  | 3 |  |  | 3 |  |  |  |  |  | (8) |  |  | (7) |  |  |  | (25) |  |  | (23) |  |  |
Settlement loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 8 |  |  |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  |
Net periodic credit |  | $ | (17) |  |  | $ | (18) |  |  |  | $ | (52) |  |  | $ | (57) |  |  |  |  |  | $ | (23) |  |  | $ | (22) |  |  |  | $ | (68) |  |  | $ | (66) |  |  |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic credit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 6 |  |  | $ | 7 |  |  |  | $ | 18 |  |  | $ | 20 |  |  |  |  |  | $ | 2 |  |  | $ | 2 |  |  |  | $ | 6 |  |  | $ | 8 |  |  |
Interest cost |  | 26 |  |  | 25 |  |  |  | 77 |  |  | 74 |  |  |  |  |  | 11 |  |  | 11 |  |  |  | 32 |  |  | 31 |  |  |
Expected return on plan assets |  | (54) |  |  | (56) |  |  |  | (162) |  |  | (166) |  |  |  |  |  | (26) |  |  | (26) |  |  |  | (78) |  |  | (80) |  |  |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 2 |  |  | 3 |  |  |  | 7 |  |  | 8 |  |  |  |  |  | — |  |  | 1 |  |  |  | 2 |  |  | 3 |  |  |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  |  | 3 |  |  | 3 |  |  |  |  |  | (8) |  |  | (8) |  |  |  | (25) |  |  | (23) |  |  |
Settlement loss |  | 3 |  |  | 3 |  |  |  | 8 |  |  | 8 |  |  |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  |
Net periodic credit |  | $ | (16) |  |  | $ | (17) |  |  |  | $ | (49) |  |  | $ | (53) |  |  |  |  |  | $ | (21) |  |  | $ | (20) |  |  |  | $ | (63) |  |  | $ | (61) |  |  |
In Consumers’ electric and gas rate cases, the MPSC approved a mechanism allowing Consumers to defer for future recovery or refund pension and OPEB expenses above or below the amounts used to set existing rates. Amounts deferred will be collected from or refunded to customers over ten years. At September 30, 2025, CMS Energy, including Consumers, had deferred $1 million of pension costs and $7 million of OPEB credits under this mechanism related to 2025 expense. At September 30, 2024, CMS Energy, including Consumers, had deferred $12 million of pension credits and $8 million of OPEB credits under this mechanism related to 2024 expense.

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