v3.26.1
Retirement Benefits (Tables)
 6 Months Ended
Jun. 30, 2026
Defined Benefit Plan Disclosure [Line Items]  
Schedule of Net Benefit 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 PlansOPEB Plan
Three Months EndedSix Months EndedThree Months EndedSix Months Ended
June 3020262025202620252026202520262025
CMS Energy, including Consumers
Net periodic credit
Service cost$6 $7 $12 $13 $2 $2 $4 $4 
Interest cost25 27 50 54 9 11 19 22 
Expected return on plan assets(59)(57)(119)(114)(31)(28)(62)(56)
Amortization of:
Net loss3 2 7 5 — 1 — 2 
Prior service cost (credit)1 1 2 2 (8)(8)(16)(17)
Settlement loss2 2 5 5 — — — — 
Net periodic credit$(22)$(18)$(43)$(35)$(28)$(22)$(55)$(45)
Consumers
Net periodic credit
Service cost$6 $6 $12 $12 $2 $2 $4 $4 
Interest cost24 25 47 51 9 11 19 21 
Expected return on plan assets(56)(54)(112)(108)(29)(26)(58)(52)
Amortization of:
Net loss3 3 6 5 — 1 — 2 
Prior service cost (credit)1 1 2 2 (8)(9)(16)(17)
Settlement loss2 2 5 5 — — — — 
Net periodic credit$(20)$(17)$(40)$(33)$(26)$(21)$(51)$(42)
Consumers Energy Company  
Defined Benefit Plan Disclosure [Line Items]  
Schedule of Net Benefit 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 PlansOPEB Plan
Three Months EndedSix Months EndedThree Months EndedSix Months Ended
June 3020262025202620252026202520262025
CMS Energy, including Consumers
Net periodic credit
Service cost$6 $7 $12 $13 $2 $2 $4 $4 
Interest cost25 27 50 54 9 11 19 22 
Expected return on plan assets(59)(57)(119)(114)(31)(28)(62)(56)
Amortization of:
Net loss3 2 7 5 — 1 — 2 
Prior service cost (credit)1 1 2 2 (8)(8)(16)(17)
Settlement loss2 2 5 5 — — — — 
Net periodic credit$(22)$(18)$(43)$(35)$(28)$(22)$(55)$(45)
Consumers
Net periodic credit
Service cost$6 $6 $12 $12 $2 $2 $4 $4 
Interest cost24 25 47 51 9 11 19 21 
Expected return on plan assets(56)(54)(112)(108)(29)(26)(58)(52)
Amortization of:
Net loss3 3 6 5 — 1 — 2 
Prior service cost (credit)1 1 2 2 (8)(9)(16)(17)
Settlement loss2 2 5 5 — — — — 
Net periodic credit$(20)$(17)$(40)$(33)$(26)$(21)$(51)$(42)