While more than two-thirds (69 per cent) of private sector workers in the U.S. have access to an employer-sponsored retirement savings plan, just half (52 per cent) of these employees says they choose to participate, according to a new survey by

The survey, which polled 1,000 workers, found more than a quarter (28 per cent) said they have nothing saved for retirement, including 39 per cent who said they aren’t contributing to a retirement fund and 30 per cent who said they don’t think they’ll ever be able to retire.

A quarter of employees said they think they can retire with less than US$500,000, while a similar percentage said they think it will take somewhere between $500,000 and $1 million. Fewer than a third (30 per cent) said they expect their retirement to cost even higher in the seven figures.

Read: Survey finds 56% of U.S. employees expecting less than $500K in retirement savings

While nearly three-quarters (71 per cent) are heading toward retirement with five-figure nest eggs at best, the survey noted 10 per cent have saved $50,000 to $100,000, a third (33 per cent) have less than $50,000 and 28 per cent have saved nothing for retirement.

Indeed, 28 per cent of adults aged 18 to 24 have no retirement savings and between 25 per cent and 35 per cent of employees aged 18 to 64 reported having nothing saved for their golden years.

Two-fifths (39 per cent) said they contribute nothing to tax-advantaged retirement accounts, such as a 401(k), while just 13 per cent said they contribute between one and three per cent of their income. Another 13 per cent noted they contribute between four and six per cent.

Read: Half of U.S. workers say rising costs, financial crises impacting retirement savings: survey