v3.25.4
Risk Management - Disclosure of concentrations of credit risk by industry and geography (Details) - GBP (£)
£ in Millions
Dec. 31, 2025
Dec. 31, 2024
Disclosure of geographical areas [line items]    
Loans and advances £ 1,232,975 £ 1,204,773
Contingent liabilities    
Disclosure of geographical areas [line items]    
Exposure to credit risk on loan commitments and financial guarantee contracts 25,567 25,393
Loan commitments    
Disclosure of geographical areas [line items]    
Exposure to credit risk on loan commitments and financial guarantee contracts 333,859 338,191
Net gains on financial instruments designated at fair value | Gross exposure    
Disclosure of geographical areas [line items]    
Exposure to credit risk on loan commitments and financial guarantee contracts 22,197 16,338
Total loans and advances at amortised cost including debt securities    
Disclosure of geographical areas [line items]    
Loans and advances 205,939 195,054
Total loans and advances at amortised cost including debt securities | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 205,939 195,054
Total loans and advances at amortised cost including debt securities | Financial assets at amortised cost | Gross exposure    
Disclosure of geographical areas [line items]    
Loans and advances 209,575 198,494
Loans and advances at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 150,786 144,827
Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 150,786 144,827
Loans and advances at amortised cost | Financial assets at amortised cost | Gross exposure    
Disclosure of geographical areas [line items]    
Loans and advances 154,403 148,247
Debt securities at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 55,153 50,227
Debt securities at amortised cost | Financial assets at amortised cost | Gross exposure    
Disclosure of geographical areas [line items]    
Loans and advances 55,172 50,247
Off-balance sheet    
Disclosure of geographical areas [line items]    
Loans and advances 359,824 364,004
Off-balance sheet | Contingent liabilities    
Disclosure of geographical areas [line items]    
Loans and advances 25,728 25,577
Off-balance sheet | Loan commitments    
Disclosure of geographical areas [line items]    
Loans and advances 334,096 338,427
Agriculture, Food and Forest Products | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 135 112
Mining and Quarrying | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,265 1,404
Manufacturing | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 5,771 5,763
Government and central bank | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 752 564
Banks | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 9,036 8,778
Energy and water | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 3,862 2,958
Materials and Building | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 16,552 14,687
Wholesale and retail distribution and leisure | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 7,520 7,672
Transport and storage | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,367 1,336
Home Loans | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 4,952 4,956
Business and other services | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 23,202 21,719
Other Financial Institutions | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 51,717 51,211
Cards, unsecured loans and other personal lending | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 24,655 23,667
United Kingdom | Total loans and advances at amortised cost including debt securities    
Disclosure of geographical areas [line items]    
Loans and advances 72,050 68,218
United Kingdom | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 53,874 52,396
United Kingdom | Debt securities at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 18,176 15,822
United Kingdom | Off-balance sheet    
Disclosure of geographical areas [line items]    
Loans and advances 55,783 53,032
United Kingdom | Off-balance sheet | Contingent liabilities    
Disclosure of geographical areas [line items]    
Loans and advances 6,780 6,442
United Kingdom | Off-balance sheet | Loan commitments    
Disclosure of geographical areas [line items]    
Loans and advances 49,003 46,590
United Kingdom | Agriculture, Food and Forest Products | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 61 112
United Kingdom | Mining and Quarrying | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 679 506
United Kingdom | Manufacturing | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 3,500 3,168
United Kingdom | Government and central bank | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 156 220
United Kingdom | Banks | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,151 1,212
United Kingdom | Energy and water | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 2,176 2,067
United Kingdom | Materials and Building | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 13,376 11,255
United Kingdom | Wholesale and retail distribution and leisure | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 6,085 5,931
United Kingdom | Transport and storage | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 693 519
United Kingdom | Home Loans | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 2,948 3,079
United Kingdom | Business and other services | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 12,163 11,846
United Kingdom | Other Financial Institutions | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 9,482 10,655
United Kingdom | Cards, unsecured loans and other personal lending | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,404 1,826
Americas | Total loans and advances at amortised cost including debt securities    
Disclosure of geographical areas [line items]    
Loans and advances 85,725 84,405
Americas | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 66,871 66,343
Americas | Debt securities at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 18,854 18,062
Americas | Off-balance sheet    
Disclosure of geographical areas [line items]    
Loans and advances 252,202 254,354
Americas | Off-balance sheet | Contingent liabilities    
Disclosure of geographical areas [line items]    
Loans and advances 12,320 10,742
Americas | Off-balance sheet | Loan commitments    
Disclosure of geographical areas [line items]    
Loans and advances 239,882 243,612
Americas | Agriculture, Food and Forest Products | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 0 0
Americas | Mining and Quarrying | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 357 709
Americas | Manufacturing | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,150 1,418
Americas | Government and central bank | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 0 0
Americas | Banks | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 3,435 3,573
Americas | Energy and water | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,068 401
Americas | Materials and Building | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 2,414 2,815
Americas | Wholesale and retail distribution and leisure | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 675 831
Americas | Transport and storage | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 344 421
Americas | Home Loans | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 116 110
Americas | Business and other services | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 5,610 5,196
Americas | Other Financial Institutions | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 30,760 30,788
Americas | Cards, unsecured loans and other personal lending | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 20,942 20,081
Europe | Total loans and advances at amortised cost including debt securities    
Disclosure of geographical areas [line items]    
Loans and advances 36,184 31,388
Europe | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 18,934 16,265
Europe | Debt securities at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 17,250 15,123
Europe | Off-balance sheet    
Disclosure of geographical areas [line items]    
Loans and advances 40,634 45,378
Europe | Off-balance sheet | Contingent liabilities    
Disclosure of geographical areas [line items]    
Loans and advances 5,084 5,514
Europe | Off-balance sheet | Loan commitments    
Disclosure of geographical areas [line items]    
Loans and advances 35,550 39,864
Europe | Agriculture, Food and Forest Products | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 74 0
Europe | Mining and Quarrying | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 221 189
Europe | Manufacturing | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 760 828
Europe | Government and central bank | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 118 2
Europe | Banks | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,719 1,286
Europe | Energy and water | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 294 203
Europe | Materials and Building | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 397 399
Europe | Wholesale and retail distribution and leisure | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 251 294
Europe | Transport and storage | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 205 300
Europe | Home Loans | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 832 899
Europe | Business and other services | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 4,024 3,646
Europe | Other Financial Institutions | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 8,630 7,226
Europe | Cards, unsecured loans and other personal lending | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,409 993
Others | Total loans and advances at amortised cost including debt securities    
Disclosure of geographical areas [line items]    
Loans and advances 11,980 11,043
Others | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 11,107 9,823
Others | Debt securities at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 873 1,220
Others | Off-balance sheet    
Disclosure of geographical areas [line items]    
Loans and advances 11,205 11,240
Others | Off-balance sheet | Contingent liabilities    
Disclosure of geographical areas [line items]    
Loans and advances 1,544 2,879
Others | Off-balance sheet | Loan commitments    
Disclosure of geographical areas [line items]    
Loans and advances 9,661 8,361
Others | Agriculture, Food and Forest Products | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 0 0
Others | Mining and Quarrying | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 8 0
Others | Manufacturing | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 361 349
Others | Government and central bank | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 478 342
Others | Banks | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 2,731 2,707
Others | Energy and water | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 324 287
Others | Materials and Building | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 365 218
Others | Wholesale and retail distribution and leisure | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 509 616
Others | Transport and storage | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 125 96
Others | Home Loans | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,056 868
Others | Business and other services | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 1,405 1,031
Others | Other Financial Institutions | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances 2,845 2,542
Others | Cards, unsecured loans and other personal lending | Loans and advances at amortised cost | Financial assets at amortised cost    
Disclosure of geographical areas [line items]    
Loans and advances £ 900 £ 767