Around one in seven under-45s worry they will never be able to retire, a survey has found.
Some 14.8% of people aged under 45 have this concern, according to Moneyfacts.co.uk.
Among those aged 45 to 64, 2.6% think they may never be in a position to retire.
Just over a quarter (25.9%) of those under 45 think they may not be able to retire until after the age of 70, compared with 3.8% of 45 to 64-year-olds.
While three-quarters (75%) of those surveyed aged between 45 and 64 hope to retire between the ages of 55 and 65, less than half (39.3%) of those aged under 45 have expectations of having retired by then, the research found.
Rachel Springall, a finance expert at Moneyfacts.co.uk, said: "Many younger consumers seem to be realising they can expect a later retirement, or in some cases, worry that they will never truly retire."
She said that while automatic enrolment into workplace pensions "is a welcome step towards saving for retirement, it shouldn't be assumed that the bare minimum will be sufficient to cover what individuals expect to retire on".
Ms Springall added: "According to our survey, consumers hope to retire with a pension pot that can give them 63% of their current level of income.
"However, they realistically expect to only receive 52% of this. Either way, it will require diligent saving throughout their working lives."
Minimum contributions into workplace pensions under automatic enrolment are gradually being stepped up to help people build their pension pot, with an increase on Friday last week and a further rise in April 2019.