Women retiring this year will be around £5,400 a year worse off than men finishing work in 2016, a report has found.
On average, women retiring in 2016 expect to have around £14,450 a year to live on - the highest figure for women retiring in any year since Prudential's annual survey started in 2008.
But while the situation for women is improving, the gender gap is also growing. The gap between what female and male retirees expect to have as an annual income has increased by £600 over the last year.
This is because while women typically expect to be £150 a year better off than women who retired last year, men expect to be £750 a year better off on average than men who retired in 2015 - a £600 difference between the sexes.
On average, men retiring in 2016 expect to have an annual income of £19,850 to live on - £5,400 more than women retiring this year.
Two-fifths (40%) of women retiring this year expect to have enough income to live comfortably, compared with three-fifths (60%) of men.
Despite the boost to men's retirement incomes, men retiring this year do not expect to have as much annual income as those retiring in 2008 and 2009, when the average man retiring in those years expected to have over £20,000.
The retirement incomes people expect to have are made up of the annual amounts they expect to get from savings, the state pension, private pensions and any other investments such as property.
Prudential surveyed 1,000 people planning to retire in 2016 for the latest study.
Huge changes have taken place in recent years to pension saving and retirement. Workers are gradually being automatically enrolled into pensions, amid efforts to encourage more people to save more money for their retirement.
In 2015, new pension freedoms were introduced to give people aged over 55 more flexibility over how they use their pension pot.
The freedoms mean people are no longer required to buy a retirement income called an annuity with their pension pot. There have been signs of annuity rates plummeting recently amid the market turmoil following the referendum vote to leave the EU.
Earlier this year, the state pension was also overhauled for new pensioners. The new single-tier state pension aims to sweep away some of the complexities of the old state pension system.
Usually, people will need at least 10 years of qualifying National Insurance (NI) contributions to get any state pension - and 35 years of contributions to get the full amount. Contributions could come from paying in or getting credits, for instance for caring for a family.
But according to previous analysis from Age UK, around 70,000 people in their 50s and 60s will miss out entirely on the new state pension between now and 2030.
Some 50,000 women and 20,000 men do not have the minimum number of qualifying years of NI contributions, according to the charity's analysis. The previous regime allowed people to receive at least some state pension even with only a few years of NI contributions.
Kirsty Anderson, a retirement income expert at Prudential, said: "It is possible that many women retirees were expecting to receive the new 'flat rate' state pension in full, but having received their illustrations have had to revise their retirement expectations downwards.
"It is an unfortunate fact of life that many women will reach retirement having taken breaks during their working lives that will impact the level of state pension they will receive and the size of their pension pot.
"However, there are a number of steps that anyone in this situation can take prior to giving up work to help improve their retirement prospects. These include continuing to make contributions to a pension during career breaks and making voluntary National Insurance contributions after returning to work."
Prudential's findings were released in the same week that the "triple lock", which guarantees that the state pension is uprated by a certain guaranteed minimum amount, was called into question. The policy ensures the state pension rises each year by the highest of price inflation, average earnings or 2.5%.
Prime Minister Theresa May moved to calm fears that she plans to kill off the triple lock protecting state pensions, after former pensions minister Baroness Altmann warned the cost of keeping the safeguard would be "enormous" after the slated next general election in 2020.
Lady Altmann had suggested the triple lock could be replaced with a "double lock", and argued that by dropping the promise of increasing state pensions by at least 2.5% from 2020, even if earnings and prices rise by far less than that, the Government could potentially save billions of pounds on long-term pension costs.
A Department for Work and Pensions (DWP) spokesman said : "Since 2014, the gap in retirement incomes between men and women has actually fallen by £1,300 and we are determined to continue this trend by encouraging more people to save for a secure retirement through automatic enrolment.
"Women reaching state pension age in 2016 are also estimated to receive more state pension on average over their lifetime than women ever have before."