v3.25.2
Credit risk - Narrative (Details)
£ in Millions
 6 Months Ended
Jun. 30, 2025
GBP (£)
economic_scenario
Dec. 31, 2024
GBP (£)
Credit risk    
Disclosure of financial assets [line items]    
Number of economic scenarios | economic_scenario 5  
Stress horizon period 5 years  
Impairment allowance | Post-model adjustment    
Disclosure of financial assets [line items]    
Financial assets £ (87)  
Impairment allowance | Post-model adjustment, net of significant risk transfer    
Disclosure of financial assets [line items]    
Financial assets (70)  
Impairment allowance | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (79) £ 0
Impairment allowance | Other adjustments    
Disclosure of financial assets [line items]    
Financial assets 57 29
Impairment allowance | Total loans and advances at amortised cost including debt securities | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (79) 0
Impairment allowance | Total loans and advances at amortised cost | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (78) 0
Impairment allowance | Total loans and advances at amortised cost | Economic uncertainty adjustments | Cross default risk    
Disclosure of financial assets [line items]    
Financial assets (78) 0
Impairment allowance | Total loans and advances at amortised cost | Other adjustments    
Disclosure of financial assets [line items]    
Financial assets 57 22
Impairment allowance | Retail credit cards    
Disclosure of financial assets [line items]    
Financial assets (2,371) (2,557)
Impairment allowance | Retail credit cards | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (30) 0
Impairment allowance | Retail credit cards | Economic uncertainty adjustments | Cross default risk    
Disclosure of financial assets [line items]    
Financial assets (30) 0
Impairment allowance | Retail credit cards | Other adjustments    
Disclosure of financial assets [line items]    
Financial assets 0 23
Impairment allowance | Corporate loans    
Disclosure of financial assets [line items]    
Financial assets (818) (791)
Impairment allowance | Corporate loans | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (48) 0
Impairment allowance | Corporate loans | Economic uncertainty adjustments | Cross default risk    
Disclosure of financial assets [line items]    
Financial assets (48) 0
Impairment allowance | Corporate loans | Other adjustments    
Disclosure of financial assets [line items]    
Financial assets 60 6
Impairment allowance | Debt securities at amortised cost | Economic uncertainty adjustments    
Disclosure of financial assets [line items]    
Financial assets (1) 0
Impairment allowance | Debt securities at amortised cost | Other adjustments    
Disclosure of financial assets [line items]    
Financial assets £ 0 £ 7