v3.25.4
Property, plant and equipment - Schedule of Property, Plant and Equipment (Details) - CAD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance $ 30,001 $ 30,352
Ending balance 33,541 30,001
Cost    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 88,537 86,836
Additions 4,578 4,629
Business acquisitions 3,972 266
Transfers (983) (1,279)
Retirements and disposals 2,905 1,724
Impairment (losses) reversals recognized in earnings (123) (180)
Reclassified to assets held for sale (3) (11)
Net foreign exchange differences (32)  
Ending balance 93,041 88,537
Accumulated depreciation    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance (58,536) (56,484)
Depreciation 3,861 3,758
Transfers (6)  
Retirements and disposals (2,844) (1,661)
Net foreign exchange differences (1)  
Other (46) (45)
Ending balance (59,500) (58,536)
Network infrastructure and equipment    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 23,470 23,750
Ending balance 26,143 23,470
Network infrastructure and equipment | Cost    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 76,151 74,676
Additions 1,983 2,092
Business acquisitions 3,000 72
Transfers 1,163 881
Retirements and disposals 2,791 1,484
Impairment (losses) reversals recognized in earnings (135) (85)
Reclassified to assets held for sale (1) (1)
Net foreign exchange differences (23)  
Ending balance 79,347 76,151
Network infrastructure and equipment | Accumulated depreciation    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance (52,681) (50,926)
Depreciation 3,319 3,245
Transfers 9  
Retirements and disposals (2,764) (1,447)
Net foreign exchange differences (1)  
Other (40) (43)
Ending balance (53,204) (52,681)
Land and buildings    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 4,306 4,247
Ending balance 4,817 4,306
Land and buildings | Cost    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 10,161 9,805
Additions 515 430
Business acquisitions 537 184
Transfers 3 79
Retirements and disposals 109 232
Impairment (losses) reversals recognized in earnings 12 (95)
Reclassified to assets held for sale (2) (10)
Net foreign exchange differences (4)  
Ending balance 11,113 10,161
Land and buildings | Accumulated depreciation    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance (5,855) (5,558)
Depreciation 542 513
Transfers (15)  
Retirements and disposals (80) (214)
Net foreign exchange differences 0  
Other (6) (2)
Ending balance (6,296) (5,855)
Assets under construction    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 2,225 2,355
Ending balance 2,581 2,225
Assets under construction | Cost    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 2,225 2,355
Additions 2,080 2,107
Business acquisitions 435 10
Transfers (2,149) (2,239)
Retirements and disposals 5 8
Impairment (losses) reversals recognized in earnings 0 0
Reclassified to assets held for sale 0 0
Net foreign exchange differences (5)  
Ending balance 2,581 2,225
Assets under construction | Accumulated depreciation    
Changes in property, plant and equipment, including right-of-use assets [abstract]    
Beginning balance 0 0
Depreciation 0 0
Transfers 0  
Retirements and disposals 0 0
Net foreign exchange differences 0  
Other 0 0
Ending balance $ 0 $ 0