The number of women participating in a workplace pension has increased by 70% since auto-enrolment (AE) began, analysis by Equiniti reveals.
The administration provider said Department for Work and Pensions (DWP) saving trends data showed AE has resulted in 3.5 million more women saving into workplace pension schemes.
It said, at the time of AE's introduction in 2012, fewer than 5.1 million women were contributing to a pension, with under six in ten (59%) participating. Equiniti said there were now 8.7 million, or nine in ten (88%), of eligible women saving for retirement through a workplace pension.
Equiniti propositions and solutions director Chris Connelly said, while there is clear progression in the level of female pension participation, more needs to help women increase their retirement income.
He said: "Women are still reaching retirement with significantly less in their pot than men for a number of factors such as, lower average incomes and the unequal burden of care responsibilities for both children and elderly relatives."
The DWP statistics also found that part-time and lower-earning female workers have benefitted the most from increased AE participation - and, while there was a consistently high level of participation from women earning over £30,000, just four in ten (42%) of those earning £10-20,000 and six in ten (61%) of £20-30,000 were paying into a workplace pension in 2012.
Equiniti said this has now risen to 83% and 89% respectively - noting that lower-earning women were on track to reach parity with their higher-earning counterparts in the next couple of years.
Across the same time period, the proportion of women working part-time in the private sector, participating in a workplace pension more than doubled from just over a third (36%) to four-fifths (80%).
Connelly commented: "One of the most striking features of AE's success is how it has managed to get those on lower earnings, including those just starting out in the world of work, into pensions with a low opt-out rate. It is great to see that it has had such a radical effect on part-time women in the workplace, not just full-time."
He added: "The next target is encouraging women to choose against opting out as the proportion of income they invest increases, and encourage them to take advantage of employer contributions by putting more of their own salary in."
But Connelly said pension policy and strategy could not do this on its own. He explained: "It remains vitally important to address the whole welfare agenda, including access to affordable childcare, flexible working for parents and managing the costs of long-term care in later life."