Vital support services for the elderly and vulnerable are at risk despite most councils planning to hike up bills to meet spiralling costs, town hall leaders have warned.
A 2% increase on council tax bills to boost funding for social care is set to be imposed by nine out of ten English local authorities, research has found.
But the £372 million the new fundraising powers is expected to generate will not meet the gap in funding, according to the Local Government Association.
Councillor Nick Forbes, LGA vice chair, said town halls had "no choice but to ask residents to pay more council tax" over the next few years and warned there was still a real threat of a crisis in care.
He added: "At the same time, they are warning communities that despite council tax rising, the quality and quantity of services on offer could drop, as the income will not be enough to offset the full impact of further funding reductions next year and with the national living wage bringing a significant further cost pressure from April.
"Councils will continue to do all they can to maintain the services that older and vulnerable people rely on but services supporting the elderly and disabled are at breaking point. It cannot be left to council taxpayers alone to try and fix them.
"Vulnerable members of the community still face an uncertain future next year where the dignified care and support they deserve, such as help getting dressed, fed or getting out and about, remains at risk. Vital social care services will increasingly be unable to help ease the growing pressure on the NHS and the threat of a care home crisis is still very real."
The LGA found 90% of councils with responsibility for social care are considering or have approved plans to add an extra 2% on the tax bill in 2016/17 to fund the service under new powers introduced by the Government.
Its analysis showed nine councils – City of London, Ealing, Hammersmith & Fulham, Hillingdon, Hounslow, Kensington & Chelsea, Merton, Redcar & Cleveland and Stoke-on-Trent – will not use the new precept.
Vicky McDermott, who chairs the Care and Support Alliance representing more than 75 national charities, said: "Councils have been placed into a difficult position affecting people's lives. For many people in the social care system, they will only see their lives get worse, not better. In order to alleviate a degree of suffering, the Government should bring forward the money earmarked to the Better Care Fund in the Budget.
"The Government continues to ask local councils to achieve the impossible while they ration central government funds for adult social care."
A Government spokesman said: "Supporting those most in need is an absolute priority and we have provided a £3.5 billion social care package – compared to the £2.9 billion councils said they needed.
"Councils will have almost £200 billion to spend on local services, over the lifetime of this Parliament.
"This means councils can deliver services their residents value, while council tax bills are expected to be lower in real terms by the end of this Parliament than they were in 2010."