Workers are being urged to keep track of their pension savings with a survey suggesting that 25% of over-55s have four or more pension pots.
The number of workplace pension pots in which people have savings will grow as staff become more mobile.
One in 10 of over-55s have worked in more than 10 different places during their lifetime, a survey for provider Now Pensions has suggested.
The issue has become more acute with the start of automatic enrolment.
More and more workers are automatically enrolled into a workplace pension scheme, under a new government regime.
Anyone earning more than £9,440 could be signed up to an occupational pension with every new job as a result.
The government is planning to make it easier for workers who change jobs frequently to take any small pension pot with them and merge it with their next workplace pension.
Pensions Minister Steve Webb has proposed that pension savings from auto-enrolment should automatically transfer to their new employer’s scheme, although there are fears that this could be a worse deal for some.
About a third of those asked in the Now Pensions survey said that they did not know where all their pension pots were, and had failed to inform the provider of a change of address.
“Each month The Pensions Advisory Service receives around 200 calls and queries from people who are unable to trace their pensions,” said Michelle Cracknell, chief executive of The Pensions Advisory Service.
“The number of people who spend their working life with one employer are now few and far between.”
The Department of Work and Pensions also runs a pension tracing service that locates lost pensions for individuals. It will then send details of the scheme provider’s address to allow the policyholder to gather more information.