v3.25.4
Pension schemes - Amounts recognized in the statement of financial position in respect of defined benefit pension schemes (Details) - GBP (£)
£ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of net defined benefit liability (asset)    
At start of year £ 21  
At end of year 43 £ 21
Net deferred tax liabilities on net defined benefit pension balance (9) (4)
United Kingdom    
Disclosure of net defined benefit liability (asset)    
At start of year 30  
At end of year £ 52 £ 30
Weighted average duration of defined benefit obligation 12 years 13 years
United States    
Disclosure of net defined benefit liability (asset)    
At start of year £ (9)  
At end of year £ (9) £ (9)
Weighted average duration of defined benefit obligation 9 years 9 years
Present value of defined benefit obligation    
Disclosure of net defined benefit liability (asset)    
At start of year £ (3,513) £ (3,806)
Service cost (2) (4)
Past service cost (5)  
Net interest on net defined benefit balance (188) (173)
Actuarial gains/(losses) on financial assumptions 37 321
Actuarial (losses)/gains arising from experience assumptions (19) (23)
Contributions by employees (7) (7)
Liabilities/assets transferred on settlement 140  
Benefits paid 197 195
Exchange translation differences 52 (16)
At end of year (3,308) (3,513)
Present value of defined benefit obligation | Funded schemes    
Disclosure of net defined benefit liability (asset)    
At start of year (3,348)  
At end of year (3,154) (3,348)
Present value of defined benefit obligation | Unfunded schemes    
Disclosure of net defined benefit liability (asset)    
At start of year (165)  
At end of year (154) (165)
Present value of defined benefit obligation | United Kingdom    
Disclosure of net defined benefit liability (asset)    
At start of year (2,710) (2,984)
Service cost   (1)
Past service cost (5)  
Net interest on net defined benefit balance (147) (133)
Actuarial gains/(losses) on financial assumptions 57 301
Actuarial (losses)/gains arising from experience assumptions (16) (20)
Contributions by employees (7) (7)
Benefits paid 137 134
At end of year (2,691) (2,710)
Present value of defined benefit obligation | United States    
Disclosure of net defined benefit liability (asset)    
At start of year (803) (822)
Service cost (2) (3)
Net interest on net defined benefit balance (41) (40)
Actuarial gains/(losses) on financial assumptions (20) 20
Actuarial (losses)/gains arising from experience assumptions (3) (3)
Liabilities/assets transferred on settlement 140  
Benefits paid 60 61
Exchange translation differences 52 (16)
At end of year (617) (803)
Fair value of scheme assets    
Disclosure of net defined benefit liability (asset)    
At start of year 3,544 3,771
Net interest on net defined benefit balance 191 172
Return on assets excluding amounts included in interest income 3 (273)
Contributions by employer 19 48
Contributions by employees 7 7
Liabilities/assets transferred on settlement (136)  
Benefits paid (197) (195)
Exchange translation differences (53) 14
At end of year 3,378 3,544
Fair value of scheme assets | United Kingdom    
Disclosure of net defined benefit liability (asset)    
At start of year 2,744 2,937
Net interest on net defined benefit balance 150 133
Return on assets excluding amounts included in interest income (29) (240)
Contributions by employer 13 41
Contributions by employees 7 7
Benefits paid (137) (134)
At end of year 2,748 2,744
Fair value of scheme assets | United States    
Disclosure of net defined benefit liability (asset)    
At start of year 800 834
Net interest on net defined benefit balance 41 39
Return on assets excluding amounts included in interest income 32 (33)
Contributions by employer 6 7
Liabilities/assets transferred on settlement (136)  
Benefits paid (60) (61)
Exchange translation differences (53) 14
At end of year 630 800
Net pension obligation, before impact of asset ceiling    
Disclosure of net defined benefit liability (asset)    
At start of year 31 (35)
Service cost (2) (4)
Net interest on net defined benefit balance 3 (1)
(Past service cost)/settlement credit (1)  
Contributions by employer 19 48
Actuarial (losses)/gains 21 25
Exchange translation differences (1) (2)
At end of year 70 31
Net pension obligation, before impact of asset ceiling | United Kingdom    
Disclosure of net defined benefit liability (asset)    
At start of year 34 (47)
Service cost   (1)
Net interest on net defined benefit balance 3  
(Past service cost)/settlement credit (5)  
Contributions by employer 13 41
Actuarial (losses)/gains 12 41
At end of year 57 34
Net pension obligation, before impact of asset ceiling | United States    
Disclosure of net defined benefit liability (asset)    
At start of year (3) 12
Service cost (2) (3)
Net interest on net defined benefit balance   (1)
(Past service cost)/settlement credit 4  
Contributions by employer 6 7
Actuarial (losses)/gains 9 (16)
Exchange translation differences (1) (2)
At end of year 13 (3)
Impact of asset ceiling    
Disclosure of net defined benefit liability (asset)    
At start of year (10)  
At end of year (27) (10)
Impact of asset ceiling | United Kingdom    
Disclosure of net defined benefit liability (asset)    
At start of year (4)  
At end of year (5) (4)
Impact of asset ceiling | United States    
Disclosure of net defined benefit liability (asset)    
At start of year (6)  
At end of year £ (22) £ (6)