Earnings per share - Summary of weighted average number of shares (Details) - GBP (£) £ / shares in Units, £ in Millions, shares in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Earnings per share
Profit after tax attributable to equity shareholders	£ 1,442	£ 1,049	£ 1,060
Weighted average number of shares	9,142.0	9,235.0	9,235.0
Less: weighted average number of treasury shares and shares held by EBTs	(10.0)	(2.0)
Basic weighted average number of shares - used for basic earnings per share	9,132.0	9,233.0	9,235.0
Effect of dilutive potential shares	43.0	30.0	4.0
Diluted weighted average number of shares	9,175.0	9,263.0	9,239.0
Basic earnings per share (pence)	£ 0.158	£ 0.114	£ 0.115
Diluted earnings per share (pence)	£ 0.157	£ 0.113	£ 0.115
Number of shares held by employee benefit trust	0.6	10.4	0.2

Number of shares held by employee benefit trust

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- Definition

Weighted average number of treasury shares and shares held by employee benefit trust during the period.

+ References

No definition available.

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- Definition

Weighted average shares, before effect of treasury shares

+ References

No definition available.

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- Definition

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

+ References

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- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator) divided by the weighted average number of ordinary shares outstanding during the period (the denominator).

+ References

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- Definition

The amount of profit (loss) attributable to ordinary equity holders of the parent entity (the numerator), divided by the weighted average number of ordinary shares outstanding during the period (the denominator), both adjusted for the effects of all dilutive potential ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

+ References

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- Definition

The potential dilutive effect on the weighted average number of ordinary shares that relates to the assumed conversion of the entity’s instruments. It represents the aggregate of the reconciliation amounts for all classes of instruments that reflect dilutive effect on weighted average number of ordinary shares.

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- Definition

The profit (loss) attributable to ordinary equity holders of the parent entity. [Refer: Profit (loss)]

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- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

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