v3.25.4
Structured entities - Narrative (Details)
entity in Thousands, £ in Millions
 12 Months Ended
Dec. 31, 2025
GBP (£)
entity
Dec. 31, 2024
GBP (£)
entity
Disclosure of unconsolidated structured entities [line items]    
Number of structured entities | entity 8 5
Notional contract amount £ 100,079,291 £ 83,792,768
Loans and advances 1,232,975 1,204,773
Assets transferred to sponsored unconsolidated structured entities 1,060 890
Employee benefit and other trusts    
Disclosure of unconsolidated structured entities [line items]    
Undrawn borrowing facilities £ 4,000 4,000
Securitisation vehicles | Debt securities | Not later than three months    
Disclosure of unconsolidated structured entities [line items]    
Maturity period 90 days  
Unconsolidated structured entities | Derivative financial instruments    
Disclosure of unconsolidated structured entities [line items]    
Notional contract amount £ 641,837 712,793
Contractual backstop liquidity facilities | CP's and medium-term note conduits    
Disclosure of unconsolidated structured entities [line items]    
Undrawn borrowing facilities £ 21,000 £ 23,900