v3.26.1
PROVISIONS - Summary of Provisions Reconciliation (Details) - GBP (£)
£ in Millions
 3 Months Ended 6 Months Ended
Mar. 31, 2026
Jun. 30, 2026
Jun. 30, 2025
Disclosure of other provisions [line items]      
Beginning balance £ 683 £ 683  
Additional provisions   505  
Provisions released   (5)  
Utilisation and other   (292)  
Reclassification from provisions to other assets   59  
Ending balance   950  
Customer remediation - Motor      
Disclosure of other provisions [line items]      
Beginning balance 461 461  
Additional provisions   179  
Provisions released   0  
Utilisation and other   (17)  
Reclassification from provisions to other assets   0  
Ending balance 633 623  
Restructuring      
Disclosure of other provisions [line items]      
Beginning balance 21 21  
Additional provisions   95  
Provisions released   0  
Utilisation and other   (44)  
Reclassification from provisions to other assets   0  
Ending balance   72  
Property      
Disclosure of other provisions [line items]      
Beginning balance 31 31  
Additional provisions   9  
Provisions released   0  
Utilisation and other   (5)  
Reclassification from provisions to other assets   0  
Ending balance   35  
Other - restructuring and specific provisions      
Disclosure of other provisions [line items]      
Beginning balance 10 10  
Additional provisions   85  
Provisions released   (2)  
Utilisation and other   (92)  
Reclassification from provisions to other assets   0  
Ending balance   1  
ECL on undrawn facilities and guarantees      
Disclosure of other provisions [line items]      
Beginning balance 83 83  
Additional provisions   6  
Provisions released   (3)  
Utilisation and other   0  
Reclassification from provisions to other assets   0  
Ending balance   86  
Regulatory levies and fees      
Disclosure of other provisions [line items]      
Beginning balance 6 6  
Additional provisions   83 £ 93
Provisions released   0  
Utilisation and other   (18)  
Reclassification from provisions to other assets   0  
Ending balance   71  
Bank Levy      
Disclosure of other provisions [line items]      
Beginning balance 19 19  
Additional provisions   0  
Provisions released   0  
Utilisation and other   (59)  
Reclassification from provisions to other assets   59  
Ending balance   19  
Litigation and other regulatory      
Disclosure of other provisions [line items]      
Beginning balance 38 38  
Additional provisions   0  
Provisions released   0  
Utilisation and other   (6)  
Reclassification from provisions to other assets   0  
Ending balance   32  
Customer remediation - other      
Disclosure of other provisions [line items]      
Beginning balance 7 7  
Additional provisions   0  
Provisions released   0  
Utilisation and other   (1)  
Reclassification from provisions to other assets   0  
Ending balance   6  
Other - fraud and operational losses      
Disclosure of other provisions [line items]      
Beginning balance £ 7 7  
Additional provisions   48  
Provisions released   0  
Utilisation and other   (50)  
Reclassification from provisions to other assets   0  
Ending balance   £ 5