Assets pledged, collateral received and assets transferred - Disclosure of recourse to transferred assets (Details) - GBP (£) £ in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred assets	£ 233,617	£ 247,018
Associated liabilities	(118,697)	(121,751)
Securitisation vehicles
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred assets	7,402	7,997
Associated liabilities	(929)	(1,575)
Transferred assets, fair value	7,458	8,560
Associated liabilities, fair value	(933)	(1,579)
Other
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred assets	5,834	7,697
Associated liabilities	(5,583)	(7,271)
Other \| Securitisation vehicles
Disclosure of transferred financial assets that are not derecognised in their entirety [line items]
Transferred assets	5,879	6,575
Associated liabilities	(929)	(1,575)
Transferred assets, fair value	5,935	7,158
Associated liabilities, fair value	(933)	(1,579)
Net position	£ 5,002	£ 5,579

The amount of transferred financial assets that the entity continues to recognise in full. [Refer: Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
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-IssueDate 2025-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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The amount of liabilities associated with transferred financial assets that the entity continues to recognise in full. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2025-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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The fair value of financial liabilities associated with transferred financial assets that are not derecognised in their entirety. [Refer: Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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The difference between the fair value of transferred financial assets that have not been derecognised in their entirety and their associated liabilities. [Refer: Financial assets]

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The fair value of transferred financial assets that are not derecognised in their entirety. [Refer: Financial assets]

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