Pensions - Investment strategy (Details) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Pensions
Derivatives notional (£bn)		£ 13,925,000
Fair value of assets	£ 78,904	99,545
Fair value of liabilities	72,395	94,047
Interest rate swaps
Pensions
Derivatives notional (£bn)	6,533,000	7,201,000
Fair value of assets	33,807	39,039
Fair value of liabilities	£ 27,424	£ 32,992
Main Pension Scheme
Pensions
Percentage of total plan assets	91.00%	91.00%
Equities	6.80%	7.80%
Index-linked bonds	36.70%	37.70%
Government bonds	13.30%	18.40%
Corporate and other bonds	25.60%	22.00%
Real estate	4.50%	6.00%
Derivatives	2.70%	8.20%
Cash and other assets	10.40%	(0.10%)
Total	100.00%	100.00%
Percentage of collateral	128.00%
Maximum percentage of indirect investment by trustees	5.00%
Main Pension Scheme \| Quoted plan assets
Pensions
Equities	0.10%	0.10%
Index-linked bonds	36.70%	37.70%
Government bonds	13.30%	18.40%
Corporate and other bonds	19.20%	15.30%
Total	69.30%	71.50%
Main Pension Scheme \| Unquoted plan assets
Pensions
Equities	6.70%	7.70%
Corporate and other bonds	6.40%	6.70%
Real estate	4.50%	6.00%
Derivatives	2.70%	8.20%
Cash and other assets	10.40%	(0.10%)
Total	30.70%	28.50%
Main Pension Scheme \| Swap
Pensions
Derivatives notional (£bn)	£ 81,000	£ 124,000
Derivatives, amount contributed to fair value of plan assets	714	2,642
Main Pension Scheme \| Inflation rate swaps
Pensions
Derivatives notional (£bn)	29,000	21,000
Fair value of assets	1,929	1,873
Fair value of liabilities	940	990
Main Pension Scheme \| Interest rate swaps
Pensions
Derivatives notional (£bn)	52,000	103,000
Fair value of assets	3,121	14,317
Fair value of liabilities	3,394	12,546
Main Pension Scheme \| Currency forwards
Pensions
Derivatives notional (£bn)	13,000	12,000
Fair value of assets	235	310
Fair value of liabilities	34	113
Main Pension Scheme \| Equity and bond put options
Pensions
Fair value of assets		2
Fair value of liabilities	4	70
Main Pension Scheme \| Other
Pensions
Derivatives notional (£bn)	1,000	1,000
Fair value of assets	8	14
Fair value of liabilities	20	£ 19
AA section of the group pension fund
Pensions
Bulk annuity policy, amount contributed to fair value of plan assets	£ 546
Percentage of defined benefit obligation covered by value of bulk annuity policy	99.00%
Residual assets, amount contributed to fair value of plan assets	£ 145

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_55&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_DerivativeFinancialAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of financial liabilities classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

+ References

+ Details

Name:	ifrs-full_DerivativeFinancialLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount derivatives contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]; Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 142
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_142_e&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_DerivativesAmountContributedToFairValueOfPlanAssets
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage derivatives contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]] [Contrast: Derivatives, amount contributed to fair value of plan assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 142
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_142_e&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_DerivativesPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

Name:	ifrs-full_DisclosureOfDefinedBenefitPlansLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage equity instruments contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]] [Contrast: Equity instruments, amount contributed to fair value of plan assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 142
-Subparagraph b
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_142_b&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_EquityInstrumentsPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2023-01-01
-Paragraph 112
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2023-en-r&anchor=para_112_c&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_NotionalAmount
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage real estate contributes to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [member]] [Contrast: Real estate, amount contributed to fair value of plan assets]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2023-01-01
-Paragraph 142
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2023-en-r&anchor=para_142_d&doctype=Standard
-URIDate 2023-03-23

+ Details

Name:	ifrs-full_RealEstatePercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Bulk annuity policy, amount contributed to fair value of plan assets

+ References

No definition available.

+ Details

Name:	nwg_BulkAnnuityPolicyAmountContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of Cash and other assets contribution as a percentage of total plan assets.

+ References

No definition available.

+ Details

Name:	nwg_CashAndOtherAssetsPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of Corporate and other bonds contribution as a percentage of total plan assets.

+ References

No definition available.

+ Details

Name:	nwg_CorporateAndOtherBondsPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of total plan assets held.

+ References

No definition available.

+ Details

Name:	nwg_DefinedBenefitPlanPercentageOfTotalPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of Government fixed interest bonds contribution as a percentage of total plan assets.

+ References

No definition available.

+ Details

Name:	nwg_GovernmentFixedInterestBondsPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of Index-linked bonds contribution as a percentage of total plan assets.

+ References

No definition available.

+ Details

Name:	nwg_IndexLinkedBondsPercentageContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of defined benefit obligation covered by value of bulk annuity policy

+ References

No definition available.

+ Details

Name:	nwg_PercentageOfDefinedBenefitObligationCoveredByValueOfBulkAnnuityPolicy
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The percentage of financial assets pledged as collateral for liabilities.

+ References

No definition available.

+ Details

Name:	nwg_PercentageOfFinancialAssetsPledgedAsCollateralForLiabilitiesOrContingentLiabilities
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Total contribution percentage of plan assets.

+ References

No definition available.

+ Details

Name:	nwg_PlanAssetsPercentageContributionsToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Residual assets, amount contributed to fair value of plan assets

+ References

No definition available.

+ Details

Name:	nwg_ResidualAssetsAmountContributedToFairValueOfPlanAssets
Namespace Prefix:	nwg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The percentage of maximum threshold limit for indirect investments in the group defined benefit schemes by trustees.

+ References

No definition available.

+ Details

Name:	nwg_TrusteesMaximumThresholdLimitForIndirectInvestmentInGroupDefinedBenefitSchemesPercentage
Namespace Prefix:	nwg_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_InterestRateSwapContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_DefinedBenefitPlansAxis=nwg_MainSectionOfRoyalBankOfScotlandGroupPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_NetDefinedBenefitLiabilityAssetAxis=nwg_QuotedPlanAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_NetDefinedBenefitLiabilityAssetAxis=nwg_UnquotedPlanAssetsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=ifrs-full_SwapContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=nwg_InflationRateSwapsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=nwg_CurrencyForwardsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=nwg_EquityAndBondPutOptionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_ClassesOfFinancialInstrumentsAxis=nwg_OtherDerivativeInstrumentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_DefinedBenefitPlansAxis=nwg_AaSectionOfGroupPensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: