v3.26.1
Employee retirement benefits (Tables)
 6 Months Ended
Jun. 30, 2026
Retirement Benefits [Abstract]  
Schedule of net benefit costs
The components of net benefit cost were as follows:
 
       Second Quarter
       Six Months
       to June 30
millions of Canadian dollars2026 2025 2026 2025 
Pension benefits:
Service cost44 46 87 93 
Interest cost95 91 190 184 
Expected return on plan assets(100)(98)(201)(197)
Amortization of prior service cost6 8 13 14 
Amortization of actuarial loss (gain)— 3 — 6 
Net benefit cost45 50 89 100 
Other postretirement benefits:   
Service cost1 1 2 2 
Interest cost5 6 11 11 
Amortization of prior service cost (credit)(1)(1)(2)(2)
Amortization of actuarial loss (gain)(2)(3)(5)(5)
Curtailment loss (gain)(1)— (1)— 
Net benefit cost2 3 5 6