v3.25.2
Report of the directors financial review risk report - Summary of financial instruments to which the impairment requirements in IFRS 9 are applied (Details) - USD ($)
Jun. 30, 2025
Dec. 31, 2024
Disclosure of financial assets [line items]    
Financial assets and off-balance sheet loan commitments $ 2,687,726,000,000 $ 2,497,173,000,000
Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 166,209,000,000 153,973,000,000
Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 402,487,000,000 353,855,000,000
Loans and advances to customers    
Disclosure of financial assets [line items]    
Financial assets 981,722,000,000 930,658,000,000
Loans and advances to customers | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 981,722,000,000 930,658,000,000
Loans and advances to banks    
Disclosure of financial assets [line items]    
Financial assets 107,582,000,000 102,039,000,000
Loans and advances to banks | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 107,582,000,000 102,039,000,000
Other financial assets measured at amortised cost | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 890,508,000,000 828,488,000,000
Debt instruments measured at FVOCI | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 144,966,000,000 131,825,000,000
Gross carrying amount    
Disclosure of financial assets [line items]    
Financial assets and off-balance sheet loan commitments 2,698,402,000,000 2,507,370,000,000
Gross carrying amount | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 2,698,402,000,000 2,507,370,000,000
Gross carrying amount | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 402,550,000,000 353,909,000,000
Gross carrying amount | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 708,310,000,000 636,365,000,000
Financial assets and off-balance sheet loan commitments 2,698,402,000,000 2,507,370,000,000
Gross carrying amount | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 1,990,092,000,000 1,871,005,000,000
Gross carrying amount | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 112,278,000,000 110,540,000,000
Financial assets and off-balance sheet loan commitments 406,253,000,000 414,859,000,000
Gross carrying amount | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 293,975,000,000 304,319,000,000
Gross carrying amount | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 107,960,000,000 91,787,000,000
Financial assets and off-balance sheet loan commitments 517,214,000,000 468,755,000,000
Gross carrying amount | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 409,254,000,000 376,968,000,000
Gross carrying amount | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 370,002,000,000 320,383,000,000
Financial assets and off-balance sheet loan commitments 1,356,383,000,000 1,225,413,000,000
Gross carrying amount | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 986,381,000,000 905,030,000,000
Gross carrying amount | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 117,845,000,000 113,464,000,000
Financial assets and off-balance sheet loan commitments 346,842,000,000 325,679,000,000
Gross carrying amount | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 228,997,000,000 212,215,000,000
Gross carrying amount | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 225,000,000 191,000,000
Financial assets and off-balance sheet loan commitments 71,710,000,000 72,664,000,000
Gross carrying amount | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 71,485,000,000 72,473,000,000
Gross carrying amount | Assets held for sale | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 5,080,000,000 3,273,000,000
Gross carrying amount | Assets held for sale | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Gross carrying amount | Assets held for sale | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 9,000,000 5,000,000
Gross carrying amount | Assets held for sale | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 1,897,000,000 670,000,000
Gross carrying amount | Assets held for sale | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 3,171,000,000 2,595,000,000
Gross carrying amount | Assets held for sale | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 3,000,000 3,000,000
Gross carrying amount | Loans and advances to customers | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 991,865,000,000 940,373,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 991,865,000,000 940,373,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 233,677,000,000 238,416,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 301,611,000,000 269,141,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 307,233,000,000 287,842,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 149,110,000,000 137,789,000,000
Gross carrying amount | Loans and advances to customers | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 234,000,000 7,185,000,000
Gross carrying amount | Loans and advances to banks | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 107,597,000,000 102,052,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 107,597,000,000 102,052,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 12,145,000,000 13,034,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 6,779,000,000 7,505,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 67,285,000,000 63,524,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 18,386,000,000 15,713,000,000
Gross carrying amount | Loans and advances to banks | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 3,002,000,000 2,276,000,000
Gross carrying amount | Other financial assets measured at amortised cost | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 890,630,000,000 828,580,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 890,630,000,000 828,580,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 48,153,000,000 52,869,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 100,864,000,000 100,322,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 611,863,000,000 553,664,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 61,501,000,000 58,713,000,000
Gross carrying amount | Other financial assets measured at amortised cost | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 68,249,000,000 63,012,000,000
Gross carrying amount | Other financial assets measured at amortised cost | Assets held for sale | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 2,800,000,000 2,100,000,000
Gross carrying amount | Other financial assets measured at amortised cost | Assets held for sale | IFRS 9 | German private banking business | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 3,700,000,000 2,200,000,000
Gross carrying amount | Other financial assets measured at amortised cost | Assets held for sale | IFRS 9 | South Africa | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 800,000,000 400,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 246,360,000,000 267,674,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 6,228,000,000 5,565,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 52,987,000,000 63,981,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 167,701,000,000 177,095,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 18,745,000,000 20,260,000,000
Gross carrying amount | – cash and balances at central banks | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 699,000,000 773,000,000
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 42,592,000,000 42,293,000,000
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Gross carrying amount | – Hong Kong Government certificates of indebtedness | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 42,592,000,000 42,293,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9    
Disclosure of financial assets [line items]    
Financial assets 94,957,000,000 49,289,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 283,204,000,000 252,549,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 4,020,000,000 2,896,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 19,322,000,000 13,188,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 253,279,000,000 229,672,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 5,518,000,000 5,844,000,000
Gross carrying amount | – reverse repurchase agreements – non-trading | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 1,065,000,000 949,000,000
Gross carrying amount | – financial investments | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 166,223,000,000 153,982,000,000
Gross carrying amount | – financial investments | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 33,016,000,000 40,345,000,000
Gross carrying amount | – financial investments | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 25,836,000,000 20,072,000,000
Gross carrying amount | – financial investments | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 64,104,000,000 56,537,000,000
Gross carrying amount | – financial investments | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 27,829,000,000 25,059,000,000
Gross carrying amount | – financial investments | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 15,438,000,000 11,969,000,000
Gross carrying amount | Other assets | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 147,171,000,000 108,809,000,000
Gross carrying amount | Other assets | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 4,889,000,000 4,063,000,000
Gross carrying amount | Other assets | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 2,710,000,000 3,076,000,000
Gross carrying amount | Other assets | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 124,882,000,000 89,690,000,000
Gross carrying amount | Other assets | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 6,238,000,000 4,955,000,000
Gross carrying amount | Other assets | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 8,452,000,000 7,025,000,000
Gross carrying amount | Loans and other credit-related commitments | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 691,705,000,000 619,367,000,000
Gross carrying amount | Financial guarantees | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 16,605,000,000 16,998,000,000
Gross carrying amount | Debt instruments measured at FVOCI | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 395,908,000,000 346,124,000,000
Gross carrying amount | Debt instruments measured at FVOCI | Hong Kong | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 138,366,000,000 128,568,000,000
Gross carrying amount | Debt instruments measured at FVOCI | UK | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 31,888,000,000 26,405,000,000
Gross carrying amount | Debt instruments measured at FVOCI | CIB | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 159,488,000,000 137,538,000,000
Gross carrying amount | Debt instruments measured at FVOCI | IWPB | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 58,149,000,000 51,516,000,000
Gross carrying amount | Debt instruments measured at FVOCI | Corporate Centre | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets 8,017,000,000 2,097,000,000
Gross carrying amount | Loans and advances to customers and banks | IFRS 9 | Discontinued operations | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 2,300,000,000 1,100,000,000
Allowance for ECL    
Disclosure of financial assets [line items]    
Financial assets and off-balance sheet loan commitments (10,676,000,000) (10,197,000,000)
Allowance for ECL | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (10,676,000,000) (10,197,000,000)
Allowance for ECL | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (63,000,000) (54,000,000)
Allowance for ECL | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (396,000,000) (377,000,000)
Financial assets and off-balance sheet loan commitments (10,676,000,000) (10,197,000,000)
Allowance for ECL | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (10,280,000,000) (9,820,000,000)
Allowance for ECL | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (34,000,000) (31,000,000)
Financial assets and off-balance sheet loan commitments (3,595,000,000) (3,265,000,000)
Allowance for ECL | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (3,561,000,000) (3,234,000,000)
Allowance for ECL | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (117,000,000) (119,000,000)
Financial assets and off-balance sheet loan commitments (2,122,000,000) (1,978,000,000)
Allowance for ECL | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (2,005,000,000) (1,859,000,000)
Allowance for ECL | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (235,000,000) (211,000,000)
Financial assets and off-balance sheet loan commitments (3,287,000,000) (3,398,000,000)
Allowance for ECL | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (3,052,000,000) (3,187,000,000)
Allowance for ECL | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (10,000,000) (16,000,000)
Financial assets and off-balance sheet loan commitments (1,625,000,000) (1,500,000,000)
Allowance for ECL | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,615,000,000) (1,484,000,000)
Allowance for ECL | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 0 0
Financial assets and off-balance sheet loan commitments (47,000,000) (56,000,000)
Allowance for ECL | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (47,000,000) (56,000,000)
Allowance for ECL | Assets held for sale | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (11,000,000) (4,000,000)
Allowance for ECL | Assets held for sale | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | Assets held for sale | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | Assets held for sale | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (5,000,000) (4,000,000)
Allowance for ECL | Assets held for sale | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (6,000,000) 0
Allowance for ECL | Assets held for sale | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | Loans and advances to customers | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (10,143,000,000) (9,715,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (10,143,000,000) (9,715,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (3,537,000,000) (3,208,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,980,000,000) (1,848,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (2,994,000,000) (3,141,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,587,000,000) (1,464,000,000)
Allowance for ECL | Loans and advances to customers | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (45,000,000) (54,000,000)
Allowance for ECL | Loans and advances to banks | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (15,000,000) (13,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (15,000,000) (13,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) (1,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (2,000,000) (2,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (8,000,000) (7,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (3,000,000) (1,000,000)
Allowance for ECL | Loans and advances to banks | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) (2,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (122,000,000) (92,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (122,000,000) (92,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (23,000,000) (25,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (23,000,000) (9,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (50,000,000) (39,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (25,000,000) (19,000,000)
Allowance for ECL | Other financial assets measured at amortised cost | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) 0
Allowance for ECL | Other financial assets measured at amortised cost | Assets held for sale | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 200,000 300,000
Allowance for ECL | – cash and balances at central banks | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – cash and balances at central banks | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – cash and balances at central banks | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – cash and balances at central banks | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – cash and balances at central banks | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – cash and balances at central banks | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – Hong Kong Government certificates of indebtedness | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – reverse repurchase agreements – non-trading | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | – financial investments | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (14,000,000) (9,000,000)
Allowance for ECL | – financial investments | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (2,000,000) (1,000,000)
Allowance for ECL | – financial investments | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) (1,000,000)
Allowance for ECL | – financial investments | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (4,000,000) (4,000,000)
Allowance for ECL | – financial investments | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (7,000,000) (3,000,000)
Allowance for ECL | – financial investments | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 0 0
Allowance for ECL | Other assets | IFRS 9 | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (97,000,000) (79,000,000)
Allowance for ECL | Other assets | IFRS 9 | Hong Kong | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (21,000,000) (24,000,000)
Allowance for ECL | Other assets | IFRS 9 | UK | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (22,000,000) (8,000,000)
Allowance for ECL | Other assets | IFRS 9 | CIB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (41,000,000) (31,000,000)
Allowance for ECL | Other assets | IFRS 9 | IWPB | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (12,000,000) (16,000,000)
Allowance for ECL | Other assets | IFRS 9 | Corporate Centre | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) 0
Allowance for ECL | Loans and other credit-related commitments | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (352,000,000) (348,000,000)
Allowance for ECL | Financial guarantees | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets (44,000,000) (29,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (63,000,000) (54,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | Hong Kong | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (2,000,000) (1,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | UK | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (1,000,000) (1,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | CIB | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (18,000,000) (18,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | IWPB | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (15,000,000) (14,000,000)
Allowance for ECL | Debt instruments measured at FVOCI | Corporate Centre | Debt instruments at FVOCI    
Disclosure of financial assets [line items]    
Financial assets (27,000,000) (20,000,000)
Allowance for ECL | Loans and advances to customers and banks | IFRS 9 | Discontinued operations | Debt instruments measured at amortised cost    
Disclosure of financial assets [line items]    
Financial assets 11,000,000 4,000,000
Loans and other credit-related commitments    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 691,353,000,000 619,019,000,000
Loans and other credit-related commitments | Gross carrying amount    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 691,705,000,000 619,367,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 691,705,000,000 619,367,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 111,631,000,000 109,369,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 106,862,000,000 90,848,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 356,822,000,000 307,197,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 116,165,000,000 111,762,000,000
Loans and other credit-related commitments | Gross carrying amount | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 225,000,000 191,000,000
Loans and other credit-related commitments | Allowance for ECL    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (352,000,000) (348,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (352,000,000) (348,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (29,000,000) (29,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (103,000,000) (116,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (211,000,000) (187,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (9,000,000) (16,000,000)
Loans and other credit-related commitments | Allowance for ECL | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 0 0
Financial guarantees    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 16,561,000,000 16,969,000,000
Financial guarantees | Gross carrying amount    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 16,605,000,000 16,998,000,000
Financial guarantees | Gross carrying amount | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 16,605,000,000 16,998,000,000
Financial guarantees | Gross carrying amount | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 647,000,000 1,171,000,000
Financial guarantees | Gross carrying amount | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 1,098,000,000 939,000,000
Financial guarantees | Gross carrying amount | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 13,180,000,000 13,186,000,000
Financial guarantees | Gross carrying amount | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 1,680,000,000 1,702,000,000
Financial guarantees | Gross carrying amount | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments 0 0
Financial guarantees | Allowance for ECL    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (44,000,000) (29,000,000)
Financial guarantees | Allowance for ECL | IFRS 9    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (44,000,000) (29,000,000)
Financial guarantees | Allowance for ECL | IFRS 9 | Hong Kong    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (5,000,000) (2,000,000)
Financial guarantees | Allowance for ECL | IFRS 9 | UK    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (14,000,000) (3,000,000)
Financial guarantees | Allowance for ECL | IFRS 9 | CIB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (24,000,000) (24,000,000)
Financial guarantees | Allowance for ECL | IFRS 9 | IWPB    
Disclosure of financial assets [line items]    
Off-balance sheet commitments (1,000,000) 0
Financial guarantees | Allowance for ECL | IFRS 9 | Corporate Centre    
Disclosure of financial assets [line items]    
Off-balance sheet commitments $ 0 $ 0