Fair value of financial instruments - Disclosure of analysis of movements in Level 3 assets and liabilities (Details) - GBP (£)
|
12 Months Ended |
Dec. 31, 2025 |
Dec. 31, 2024 |
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Assets transferred into level 3 |
£ 700,000,000
|
£ 0
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Transfers into Level 3 of fair value hierarchy, liabilities |
(2,800,000,000)
|
0
|
| Reconciliation of changes in fair value measurement, assets (liabilities) |
|
|
| Derivative financial assets |
252,192,000,000
|
292,356,000,000
|
| Derivative financial liabilities |
(240,757,000,000)
|
(279,331,000,000)
|
| Level 3 |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Beginning balance, financial assets |
21,862,000,000
|
|
| Ending balance, financial assets |
21,354,000,000
|
21,862,000,000
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Beginning balance, financial liabilities |
(6,817,000,000)
|
|
| Ending balance, financial liabilities |
(8,005,000,000)
|
(6,817,000,000)
|
| Reconciliation of changes in fair value measurement, assets (liabilities) |
|
|
| Derivative financial assets |
1,710,000,000
|
2,073,000,000
|
| Derivative financial liabilities |
(3,065,000,000)
|
(3,181,000,000)
|
| Recurring fair value measurement | Level 3 |
|
|
| Reconciliation of changes in fair value measurement, assets (liabilities) |
|
|
| Beginning balance, Assets (liabilities) net |
15,045,000,000
|
9,962,000,000
|
| Purchases, fair value measurement, assets (liabilities) net |
8,942,000,000
|
10,507,000,000
|
| Sales, fair value measurement, assets (liabilities) net |
(5,629,000,000)
|
(3,373,000,000)
|
| Issues, fair value measurement, assets (liabilities) net |
(503,000,000)
|
(1,147,000,000)
|
| Settlements, fair value measurement, assets (liabilities) net |
(2,444,000,000)
|
(1,319,000,000)
|
| Gains (losses) recognised in other comprehensive income, fair value measurement, assets (liabilities) net |
0
|
0
|
| Transfers into Level 3 of fair value hierarchy, assets (liabilities) net |
(2,420,000,000)
|
237,000,000
|
| Transfers out of Level 3 of fair value hierarchy, assets (liabilities) net |
211,000,000
|
253,000,000
|
| Ending balance, Assets (liabilities) net |
13,349,000,000
|
15,045,000,000
|
| Derivative financial assets |
1,710,000,000
|
2,073,000,000
|
| Derivative financial liabilities |
(3,065,000,000)
|
(3,181,000,000)
|
| Recurring fair value measurement | Level 3 | Net derivatives financial instruments |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Beginning balance, financial liabilities |
(1,108,000,000)
|
(1,113,000,000)
|
| Purchases, fair value measurement, liabilities |
(447,000,000)
|
(571,000,000)
|
| Sales, fair value measurement, liabilities |
221,000,000
|
(7,000,000)
|
| Issues, fair value measurement, liabilities |
0
|
0
|
| Settlements, fair value measurement, liabilities |
0
|
(15,000,000)
|
| Total gains or losses recognised in OCI, liabilities |
0
|
0
|
| Transfers into Level 3 of fair value hierarchy, liabilities |
3,000,000
|
163,000,000
|
| Transfers out of Level 3 of fair value hierarchy, liabilities |
19,000,000
|
501,000,000
|
| Ending balance, financial liabilities |
(1,355,000,000)
|
(1,108,000,000)
|
| Recurring fair value measurement | Level 3 | Net assets (liabilities) at fair value through profit or loss, category trading income |
|
|
| Reconciliation of changes in fair value measurement, assets (liabilities) |
|
|
| Gains (losses) recognised in profit or loss, fair value measurement, assets (liabilities) net |
170,000,000
|
(153,000,000)
|
| Recurring fair value measurement | Level 3 | Net assets (liabilities) at fair value through profit or loss, category trading income | Net derivatives financial instruments |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
(44,000,000)
|
(66,000,000)
|
| Recurring fair value measurement | Level 3 | Net assets (liabilities) at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, assets (liabilities) |
|
|
| Gains (losses) recognised in profit or loss, fair value measurement, assets (liabilities) net |
(23,000,000)
|
78,000,000
|
| Recurring fair value measurement | Level 3 | Net assets (liabilities) at fair value through profit or loss, category other income | Net derivatives financial instruments |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
1,000,000
|
0
|
| Recurring fair value measurement | Level 3 | Investment property |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Beginning balance, financial assets |
9,000,000
|
2,000,000
|
| Purchases, fair value measurement, assets |
34,000,000
|
9,000,000
|
| Sales, fair value measurement, assets |
0
|
(2,000,000)
|
| Issues, fair value measurement, assets |
0
|
0
|
| Settlements, fair value measurement, assets |
0
|
0
|
| Total gains or losses recognised in OCI, assets |
0
|
0
|
| Assets transferred into level 3 |
0
|
0
|
| Transfers out of Level 3 of fair value hierarchy, assets |
0
|
0
|
| Ending balance, financial assets |
43,000,000
|
9,000,000
|
| Recurring fair value measurement | Level 3 | Investment property | Financial assets at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
0
|
0
|
| Recurring fair value measurement | Level 3 | Investment property | Financial assets at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
0
|
0
|
| Recurring fair value measurement | Level 3 | Trading portfolio liabilities |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Beginning balance, financial liabilities |
(395,000,000)
|
(368,000,000)
|
| Purchases, fair value measurement, liabilities |
(55,000,000)
|
(26,000,000)
|
| Sales, fair value measurement, liabilities |
25,000,000
|
20,000,000
|
| Issues, fair value measurement, liabilities |
0
|
0
|
| Settlements, fair value measurement, liabilities |
352,000,000
|
0
|
| Total gains or losses recognised in OCI, liabilities |
0
|
0
|
| Transfers into Level 3 of fair value hierarchy, liabilities |
(28,000,000)
|
(15,000,000)
|
| Transfers out of Level 3 of fair value hierarchy, liabilities |
12,000,000
|
1,000,000
|
| Ending balance, financial liabilities |
(87,000,000)
|
(395,000,000)
|
| Recurring fair value measurement | Level 3 | Trading portfolio liabilities | Financial liabilities at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
2,000,000
|
(7,000,000)
|
| Recurring fair value measurement | Level 3 | Trading portfolio liabilities | Financial liabilities at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
0
|
0
|
| Recurring fair value measurement | Level 3 | Financial liabilities designated at fair value |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Beginning balance, financial liabilities |
(3,241,000,000)
|
(1,212,000,000)
|
| Purchases, fair value measurement, liabilities |
0
|
(409,000,000)
|
| Sales, fair value measurement, liabilities |
29,000,000
|
0
|
| Issues, fair value measurement, liabilities |
(503,000,000)
|
(1,147,000,000)
|
| Settlements, fair value measurement, liabilities |
1,020,000,000
|
143,000,000
|
| Total gains or losses recognised in OCI, liabilities |
0
|
0
|
| Transfers into Level 3 of fair value hierarchy, liabilities |
(2,954,000,000)
|
(892,000,000)
|
| Transfers out of Level 3 of fair value hierarchy, liabilities |
753,000,000
|
350,000,000
|
| Ending balance, financial liabilities |
(4,853,000,000)
|
(3,241,000,000)
|
| Recurring fair value measurement | Level 3 | Financial liabilities designated at fair value | Financial liabilities at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
43,000,000
|
(74,000,000)
|
| Recurring fair value measurement | Level 3 | Financial liabilities designated at fair value | Financial liabilities at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, liabilities [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, liabilities |
0
|
0
|
| Recurring fair value measurement | Level 3 | Total trading portfolio assets |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Beginning balance, financial assets |
10,115,000,000
|
6,509,000,000
|
| Purchases, fair value measurement, assets |
5,810,000,000
|
5,848,000,000
|
| Sales, fair value measurement, assets |
(4,157,000,000)
|
(1,817,000,000)
|
| Issues, fair value measurement, assets |
0
|
0
|
| Settlements, fair value measurement, assets |
(1,554,000,000)
|
(865,000,000)
|
| Total gains or losses recognised in OCI, assets |
0
|
0
|
| Assets transferred into level 3 |
382,000,000
|
775,000,000
|
| Transfers out of Level 3 of fair value hierarchy, assets |
(400,000,000)
|
(326,000,000)
|
| Ending balance, financial assets |
10,347,000,000
|
10,115,000,000
|
| Recurring fair value measurement | Level 3 | Total trading portfolio assets | Financial assets at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
151,000,000
|
(9,000,000)
|
| Recurring fair value measurement | Level 3 | Total trading portfolio assets | Financial assets at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
0
|
0
|
| Recurring fair value measurement | Level 3 | Financial assets at fair value through the income statement |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Beginning balance, financial assets |
5,991,000,000
|
5,368,000,000
|
| Purchases, fair value measurement, assets |
2,705,000,000
|
2,540,000,000
|
| Sales, fair value measurement, assets |
(1,156,000,000)
|
(1,524,000,000)
|
| Issues, fair value measurement, assets |
0
|
0
|
| Settlements, fair value measurement, assets |
(1,232,000,000)
|
(582,000,000)
|
| Total gains or losses recognised in OCI, assets |
0
|
0
|
| Assets transferred into level 3 |
59,000,000
|
206,000,000
|
| Transfers out of Level 3 of fair value hierarchy, assets |
(173,000,000)
|
(73,000,000)
|
| Ending balance, financial assets |
6,186,000,000
|
5,991,000,000
|
| Recurring fair value measurement | Level 3 | Financial assets at fair value through the income statement | Financial assets at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
14,000,000
|
0
|
| Recurring fair value measurement | Level 3 | Financial assets at fair value through the income statement | Financial assets at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
(22,000,000)
|
56,000,000
|
| Recurring fair value measurement | Level 3 | Fair value through other comprehensive income |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Beginning balance, financial assets |
3,674,000,000
|
776,000,000
|
| Purchases, fair value measurement, assets |
895,000,000
|
3,116,000,000
|
| Sales, fair value measurement, assets |
(591,000,000)
|
(43,000,000)
|
| Issues, fair value measurement, assets |
0
|
0
|
| Settlements, fair value measurement, assets |
(1,030,000,000)
|
0
|
| Total gains or losses recognised in OCI, assets |
0
|
0
|
| Assets transferred into level 3 |
118,000,000
|
0
|
| Transfers out of Level 3 of fair value hierarchy, assets |
0
|
(200,000,000)
|
| Ending balance, financial assets |
3,068,000,000
|
3,674,000,000
|
| Recurring fair value measurement | Level 3 | Fair value through other comprehensive income | Financial assets at fair value through profit or loss, category trading |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
4,000,000
|
3,000,000
|
| Recurring fair value measurement | Level 3 | Fair value through other comprehensive income | Financial assets at fair value through profit or loss, category other income |
|
|
| Reconciliation of changes in fair value measurement, assets [abstract] |
|
|
| Total gains and losses in the period recognised in the income statement, assets |
£ (2,000,000)
|
£ 22,000,000
|