The study also found 88% of people with workplace pensions have at least one that remains unclaimed.
Charlotte Ransom, CEO of Netwealth, said as the cost of living crisis continues, people must optimise their savings.
She said: “Now more than ever, it is vital that consumers track down any stranded pensions that they have worked hard to earn, and that they act to recover them sooner rather than later.”
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Among workers who have lost track of a pension, 42% say that between two and five of their pots are now stranded.
Kate Smith, head of pensions at Aegon, said people lose track of their pensions due to a lack of engagement and education.
Speaking to HR magazine, she said: “Due to the nature of auto-enrolment, some people are simply unaware that they are saving in a pension, while others may not have realised how much they have saved, or that they can consolidate it with their new employer’s pension scheme. So, many pensions get left behind and forgotten about.”
Smith said HR should encourage their employees to pay greater attention to their pensions.
She added: “HR could run campaigns, with the help of their pension providers and advisers, encouraging their employees to get to know their pensions better and sign up to see their pensions online along with a wealth of information including how to consolidate old pensions.
“Pensions are a valuable workplace benefit; greater financial education in the workplace will help employees to better understand this.”
Upcoming reforms in the pension industry should also help people maximise their savings, according to Alyshia Harrington-Clark, head of DC master trusts and lifetime savings at the Pensions and Lifetime Savings Association.
Speaking to HR magazine, she said: “The development of pensions dashboards should mean savers are able to reunite with their lost pots. Although this project is not due for completion for a few years, it will help people have a better understanding of all their pension savings.”
Pension dashboards would be a centralised service for people to find and interact with their state, employer and private pensions.
Harrington-Clark added that the government held a consultation on consolidating small pots in July.
She said: “The pensions industry is working hard to reduce the circumstances where people would have a proliferation of very small pots all over the place and is working with the government on a solution."