Low-income families could see their council tax bills rise by as much as £600 a year, according to research by the Resolution Foundation think tank.
As the government relinquishes responsibility for council tax benefit support to England's 326 local authorities, it also hands down a 10% cut in grant funding for it. Councils have responded by passing on the cost in the form of decreases in council tax discounts.
The think tank says almost six million families currently on council tax benefit to help them get by on low incomes will be hit by council tax bill increases of up to £600 a year when the benefit is replaced by council tax support.
However, pensioners will be protected from the changes that will come into effect in April.
In Wales, the cost is being absorbed by the government and in Scotland it is being spread between local authorities and the government.
The Resolution Foundation, a not-for-profit research and policy group, says the increase will depend on the decision made by each council. According to the report, 39 local authorities have opted to pass on a "severe increase" to residents, whereas 51 won't pass on any costs at all.
Protect the vulnerable
Counsellor Sir Merrick Cockell, chairman of the Local Government Association, that represents councils across the country, says councils had been left with little choice but to reduce council tax discounts.
"Councils are working hard to protect the most vulnerable and needy members of society but, as we warned when the cut was first proposed by the government, this means that other benefit recipients will have to carry a larger share of the cut," he says.