The pensions gap stands at 50 per cent between the two sexes, according to figures from Prudential.
In its Class of 2011 study, the financial services provider reports that the average expected retirement income among women is £12,900.
At £19,400, the average male pension income is more than half as much again as this, at 50.4 per cent higher.
While the difference between the two stands at a sizeable £6,500 per year, there is some good news for women approaching retirement.
Over the past year alone, the pensions gap between the sexes has narrowed by £900, the study found.
Prudential's head of business development Vince Smith-Hughes says: "It is a good idea to maintain pension contributions during any career breaks and to explore making voluntary National Insurance contributions after returning to work."
With the government this week announcing a shake-up of maternity leave to allow time off work to be shared between the parents, the gender gap in career breaks could soon narrow, taking the pensions gap with it.
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