The gap between how much male and female managers are paid has widened by £500 to £10,546 in the past year, a study suggests.
Female managers are now paid an average £31,895 per year, compared with £42,441 for men doing the same job, according to the Chartered Management Institute.
Despite women's pay rising faster than men's, the CMI said it would take 98 years to gain parity at current rates.
However, junior female managers earned more than males for the first time.
According to its survey, junior women managers now earn £21,969 on average, £602 more than men at the same level.
These are typically recent graduates who are managing projects rather than teams of people, the institute said.
"Some of that I'm hoping is that younger women have become more confident and smarter at negotiating a better pay deal," Liz Field, chief executive of the Financial Services Skills Partnership, told the BBC, adding that older, more senior women could learn from their younger colleagues.
The CMI said that women's salaries had increased by 2.4% this year, compared with 2.1% for their male colleagues.
The CMI's director of policy and research, Petra Wilton, said: "While CMI is delighted that junior female executives have caught up with males at the same level, this year's salary survey demonstrates, yet again, that businesses are contributing to the persistent gender pay gap by alienating top female employees by continuing to pay men and women unequally.
"This kind of bad management is damaging UK businesses and must be addressed."
Across the nations and regions of the UK, the gender pay gap is biggest in Northern Ireland, where on average, male managers are paid £13,793 more than their female counterparts, said the CMI.
It found that the Midlands had the next largest gap, £11,346, followed by London with £11,129.
Salaries are most equal in Wales, where the pay gap is £2,441, said the CMI.
To help close the gap, Ms Wilton said the CMI wanted the government "to scrutinise organisational pay, demand more transparency from companies on pay bandings and publicly expose organisations found guilty of fuelling the gender pay gap".
However, the CMI said it was not calling for the imposition of quotas or for organisations to be forced to reveal staff salaries.
Its survey of 34,158 managers across the UK also found that more female managers (4.2%) were choosing to quit their jobs than their male colleagues (3.6%).
At the same time, exactly the same level (2.2%) of managers of both sexes had been made redundant.
Sandra Pollock, national chair of the CMI's women in management network, said: "Too often managers are male and aged 45-plus, and we are fighting an ongoing war to ensure that professions attract people based on their talent, and not their age or gender.
"The research launched today does, however, show that we have won our first battle - it is wonderful to see that the gender pay gap at junior executive level has closed - and we hope this continues as this generation climb the ranks of management."
In February, an independent report for the government told firms to more than double the number of women on their boards by 2015 or face government measures.
The report's author, former minister Lord Davies of Abersoch, urged FTSE 350 companies to boost the percentage of women at the board table to 25% by 2015.
But he stopped short of imposing quotas, unless voluntary measures fail.
Lord Davies said on Wednesday that the progress he had seen since February had been "encouraging", but more needed to be done.
"Many companies can be proud that they have set out their own targets towards achieving greater diversity on their boards, but there are others who are dragging their feet," he said.
"The rate of female appointments since March is still well below the 25% target that my panel has set, with 47% of all FTSE 250 companies continuing to have all-male boards.
He added: "There is more work to be done and the panel will be reconvening in the autumn to assess progress and agree next steps."
However, the diversity challenge for company boards encompasses race, as well as gender, according to Ms Field of the Financial Services Skills Partnership.
"We're finding within our industry that organisations are actively looking at the reasons why there isn't diversity in the boardroom," she told the BBC.
"It does impact on a firm's value, it does impact on image, and it does impact therefore on profitability."