The gap between women and men saving into their personal pension has widen by 16 per cent in the past five years, research from Salisbury House Wealth showed.
The financial advice firm analysed data on personal pensions published by the government this month and found 1.66m fewer women contribute to their pension than men compared to 1.43m in 2011/12.
This lower number, combined with their lower average contributions than men, puts women at risk of financial struggle in later life, the firm said.
The research showed 3.6m women currently contribute to their personal pensions – compared to 5.3m men.
Tim Holmes, managing director of Salisbury House Wealth, “the number of women contributing to their pensions is only half the problem”.
He said: “The amounts they are contributing is the other half.”
Salisbury House Wealth said the central problem is the gender pay gap since women occupy lower paid roles, or are paid less than their male counterparts for performing the same role.
This means women are likely to have less money leftover at the end of the month to contribute towards savings compared to men.
Auto-enrolment, which was introduced in 2012, will help address the issue but Mr Holmes said this will not go nearly far enough to help women save for the future.
At the moment the minimum total contribution is 2 per cent - 1 per cent each from the employee and employer.
From April 2018, the minimum total contribution will increase to 5 per cent and one year later it will rise again to 8 per cent.
A total of £17bn a year will be going into workplace pensions by 2019 to 2020 because of auto-enrolment.
Mr Holmes said: “Whilst workplace pensions are a step in the right direction, it is too easy for people to keep their contributions to an absolute minimum.
“Alternatively, they can opt out altogether should they feel they cannot afford to make contributions at all.
“This is something that needs be turned around or women, in particular, could face serious financial problems in retirement. This is a major reason why the gender pay gap urgently needs to be closed.”
The government is currently reviewing auto-enrolment, with a report due to be published in December.
However, it will not introduce higher contribution rates beyond the planned increases, despite warnings from industry experts that current rates will not sustain people in retirement.