Two thirds of people have no plans to put money aside to pay for the extra care they will need in old age, a survey suggests.
Social care is means-tested in England
The same proportion said they would turn to family and friends for help rather than pay privately or ask a local council.
The poll of 1,000 people was carried out by three charities campaigning for a shake-up in the social care system.
It comes as ministers prepare to draw up plans for a reform of the system.
The government announced last year that there would be a public consultation on social care with a green paper setting out firm proposals to follow.
More than £1bn a year is already spent in England providing publicly-funded social care - although many people with savings and investments have to pay for their own care after means-testing.
There are complaints that this is effectively a disincentive to save for retirement.
A steep rise in the number of people aged 85 and over is expected in the next two decades, and there are fears that the present system will not be able to cope.
The survey, by the charities Help the Aged, Carers UK and Counsel and Care, also revealed that seven out of 10 of those polled felt the government was failing to provide adequate support for people who cared for older relatives.
A majority of people who answered the survey said they would prefer to have a cash lump sum given to them so they could arrange their own care independently.
Half said that they found the current system confusing, with many not knowing whom to approach for help.
Paul Cann, from Help the Aged, said the findings should acts as an "urgent alarm call".
"Reform to the creaking social care system is now vital."
He called for a reformed system, with "fair and sustainable" funding.
"Social care has become a distress service, meeting only the needs of the poorest and most debilitated."
The "Right Care, Right Deal" campaign, launched on Friday, is calling for social care to be available to more people, with those receiving it having more choice and control over what is provided.
A report by former government adviser Derek Wanless, published last year, proposed a "partnership system" for social care, with a large increase in public funding.
Two thirds of the bill for a service would be paid for by the government, the rest equally by the state and the individual, his report said.