A report commissioned by HSBC found that workers living in the UK typically expect to spend 19 years in retirement but only have enough savings to last for the first seven years, leaving them with a 12-year shortfall.
Across the global survey, the Future of Retirement study found that people expect their savings to run out after 10 years on average.
People living in the United States said they had enough cash put by to last for 14 years during their retirement, showing the highest expectations out of the countries surveyed.
The report also warned that the UK has the biggest inter-generational drop in the number of years that retirement savings are expected to last for.
Those surveyed in the UK who have already retired said they expect their savings to last them for 13 years on average - a figure which then almost halves to seven years among the UK's next generation of retirees.
Several countries in the study - Brazil, India, China and Taiwan - bucked the trend seen in the UK, with younger people expecting their retirement savings to last longer than those of their parents.
More than one-third (36%) of Britons who are divorced or separated expect to work indefinitely, a proportion which was the highest for of all the countries surveyed and compared with an average of 20% across the globe.
A similar proportion (31%) of those who are widowed in the UK had the same expectation, compared with 23% globally.
The findings come at a time when the Government is rolling out landmark reforms to reverse a looming retirement savings crisis as people live for longer.
One million people have already been placed into workplace pensions as a result of automatic enrolment, which started last autumn with larger companies. Recent official figures showed that private pension saving slid to record lows just before the reforms were launched.
Christine Foyster, head of wealth management at HSBC, said: "People want to slow down in later life and, while some welcome the chance to stay economically active, many may not."
The survey covered more than 16,000 people in the 15 countries, which also included Australia, Canada, Egypt, France, Hong Kong, Malaysia, Mexico, Singapore and the United Arab Emirates.