Women in the EU save 40% less into their pensions on average than men, despite earning just 16% less in wages, according to a new report by Mercer.
It shows that the savings divide varies widely from one member state to another, but that half of EU countries have gender pension gaps of 30% or more, with Cyprus recording the biggest.
This is thought to have deep social and economic implications, causing many women to end up in poverty, while work performance can also be negatively affected through employees worrying about pensions.
"The pensions gap is not only an urgent challenge for governments and policy makers, but should also be at the front of employers' minds," Mercer diversity and inclusion consultant, Mandy Schreuder, said.
"Companies that acknowledge and work to close this gap could reap the benefits of increased employee engagement and productivity."
One of the primary drivers of the gender pensions gap is women being significantly under-represented at all levels of the workplace, with their participation rate in the EU 10% lower than it is for men.
The European Commission's recent proposal for a directive on work-life balance for parents and carers, including the introduction of carers' leave for dependent relatives, aims at addressing this under-representation.
Another reason for the divide is women more likely to work part-time, or take career breaks in order to take care of children, with only 10% of organisations offering retirement programmes tailored to different work patterns.
It was also found that women tend to be less confident when making financial decisions, and more cautious about taking risks than their male counterparts.
"Most retirement plans are designed for a 40-year long, continuous, full-time career with few breaks, and do not reflect womens' divergent needs," Mercer head of proposition, DC & financial wellness, Eve Read, said.
"Companies should review their benefits plans and communications through a gender lens to ensure they address the specific issues and needs of the female workforce."
"And although the root causes behind women's risk aversion and lack of financial confidence are multidimensional and complex, action-orientated financial education should be at the heart of the solution."