Trading assets and liabilities (Details) - GBP (£) £ in Millions	Jun. 30, 2021	Dec. 31, 2020
Loans
Reverse repos	£ 24,718	£ 19,404
Collateral given	12,955	18,760
Other loans	1,154	1,611
Total loans	38,827	39,775
Securities
Financial institutions and corporate	3,812	3,446
Total securities	31,368	29,215
Total	70,195	68,990
Deposits
Repos	23,720	19,036
Collateral received	17,165	23,229
Other deposits	1,646	1,804
Total deposits	42,531	44,069
Debt securities in issue	1,205	1,408
Short positions	32,111	26,779
Total	75,847	72,256
UK
Securities
Central and local government securities	5,121	4,184
USA
Securities
Central and local government securities	4,088	5,149
Other
Securities
Central and local government securities	£ 18,347	£ 16,436

The amount of instruments representing indebtedness held by the entity.

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The amount of instruments issued by the entity that represent indebtedness.

+ References

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The amount of financial assets at fair value through profit or loss classified as held for trading. A financial asset is classified as held for trading if: (a) it is acquired principally for the purpose of selling it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: At fair value [member]; Financial assets at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The amount of financial liabilities at fair value through profit or loss that meet the definition of held for trading. A financial liability is classified as held for trading if: (a) it is acquired or incurred principally for the purpose of selling or repurchasing it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: Financial liabilities at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of debt instruments held by the entity that were issued by a government. [Refer: Debt instruments held; Government [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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The amount of debt instruments held by the entity that it does not separately disclose in the same statement or note. [Refer: Debt instruments held]

+ References

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- Definition

The amount of collateral on securities borrowed.

+ References

No definition available.

+ Details

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The amount of collateral on securities lent.

+ References

No definition available.

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The amount of deposit liabilities from others held by the entity.

+ References

No definition available.

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The amount of financial liabilities classified as derivative instruments in a short position.

+ References

No definition available.

+ Details

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The amount of deposit liabilities held by the entity.

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No definition available.

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No definition available.

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No definition available.

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The amount of other trading loans held by the entity.

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No definition available.

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The amount of instruments sold with the intent to reacquire in repurchase agreements.

+ References

No definition available.

+ Details

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The amount of instruments purchased for resale in reverse repurchase agreements.

+ References

No definition available.

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- Definition

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No definition available.

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- Definition

The amount of trading loans held by the entity.

+ References

No definition available.

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