v3.25.4
Goodwill and intangible assets - Disclosure of reconciliation of changes in intangible assets and goodwill (Details) - GBP (£)
£ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period £ 1,425  
Intangible assets and goodwill, end of period 1,303 £ 1,425
Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 3,370 3,279
Additions 398 696
Disposals (159) (141)
Exchange and other movements 454 464
Intangible assets and goodwill, end of period 3,155 3,370
Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (1,945) (2,195)
Disposals 159 141
Amortisation charge (192) (187)
Impairment charge 0 (2)
Exchange and other movements (126) (298)
Intangible assets and goodwill, end of period (1,852) (1,945)
Goodwill    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 539  
Intangible assets and goodwill, end of period 509 539
Goodwill | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 607 335
Additions 0 263
Disposals 0 0
Exchange and other movements 30 (9)
Intangible assets and goodwill, end of period 577 607
Goodwill | Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (68) (68)
Disposals 0 0
Amortisation charge 0 0
Impairment charge 0 0
Exchange and other movements 0 0
Intangible assets and goodwill, end of period (68) (68)
Software | Internally generated    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 692  
Intangible assets and goodwill, end of period 651 692
Software | Internally generated | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 1,339 1,266
Additions 398 366
Disposals (156) (131)
Exchange and other movements 328 162
Intangible assets and goodwill, end of period 1,253 1,339
Software | Internally generated | Cost | BX    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Exchange and other movements 248  
Software | Internally generated | Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (647) (623)
Disposals 156 131
Amortisation charge (155) (149)
Impairment charge 0 (2)
Exchange and other movements (44) 4
Intangible assets and goodwill, end of period (602) (647)
Software | Other    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 24  
Intangible assets and goodwill, end of period 13 24
Software | Other | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 65 73
Additions 0 1
Disposals (1) (10)
Exchange and other movements 4 (1)
Intangible assets and goodwill, end of period 60 65
Software | Other | Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (41) (42)
Disposals 1 10
Amortisation charge (8) (8)
Impairment charge 0 0
Exchange and other movements (1) 1
Intangible assets and goodwill, end of period (47) (41)
Customer lists    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 97  
Intangible assets and goodwill, end of period 71 97
Customer lists | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 1,162 1,477
Additions 0 0
Disposals 0 0
Exchange and other movements 78 315
Intangible assets and goodwill, end of period 1,084 1,162
Customer lists | Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (1,065) (1,345)
Disposals 0 0
Amortisation charge (20) (25)
Impairment charge 0 0
Exchange and other movements (72) (305)
Intangible assets and goodwill, end of period (1,013) (1,065)
Licences and other    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 73  
Intangible assets and goodwill, end of period 59 73
Licences and other | Cost    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period 197 128
Additions 0 66
Disposals (2) 0
Exchange and other movements 14 (3)
Intangible assets and goodwill, end of period 181 197
Licences and other | Accumulated amortisation and impairment    
Reconciliation of changes in intangible assets and goodwill [abstract]    
Intangible assets and goodwill, beginning of period (124) (117)
Disposals 2 0
Amortisation charge (9) (5)
Impairment charge 0 0
Exchange and other movements (9) 2
Intangible assets and goodwill, end of period £ (122) £ (124)