Insurer Aviva today became one of the first City heavyweights to reveal its gender pay gap figures.
The mean gap between women and men's pay was 28.5 per cent, with bonuses 57.2 per cent apart.
The percentage is the difference between hourly rates of pay.
Aviva said the pay differential across its 16,000 UK workforce was explained by more women were employed in junior roles, while fewer women occupied senior and management positions.
The larger gap in bonuses was due to more men staffing sales and distribution roles, "which typically attract higher bonus opportunities".
Aviva chief people officer Sarah Morris said: "We welcome the introduction of gender pay gap reporting and what it sets out to achieve. Transparency makes change happen and this is a great opportunity to better understand the challenges we face, and accelerate the pace of change as part of our broader ambition for inclusivity across our group."
The insurer said it was taking steps to close its pay gap. Actions include equal parental leave for men and women, exploring smarter and flexible ways of working and expanding the firm's group-wide "women in leadership" programme.