VULNERABLE families being forced to pay a portion of their council tax for the first time is “making the poor poorer”, an anti-poverty think tank warned last night.

Around 30,800 Suffolk families will have to pay up to 9% of their 2013/14 council tax bill from Monday, the Joseph Rowntree Foundation (JRF) said, after councils were granted powers to set their own limit for the new council tax support scheme.

The average increase for a low income family in the county will be £81 a year, one of the lowest hikes in England at 42% below the national £140 average increase.

Peter Kenway, director at the New Policy Institute (NPI), which wrote the report for JRF, criticised councils for wielding the axe on poorer families.

He said: “It is making the poor poorer. It undermines all the work New Labour did to get children and the next generation above the poverty line.

“It is very tough. It’s another turn of the screw. It seems we are turning into a society where we are extremely tough on those at the bottom of the income pile.

“Local authorities are taking a risk asking for taxes that they are not going to get. It is hard to see how poorer families are going to be able to afford it without further cutting into their savings.”

In Ipswich 9,300 families who currently do not pay all of their council tax are expected to pay £83 more a year on average, contributing 9% towards the bill.

Around 3,700 affected families in St Edmundsbury will pay £83 more annually with a 8.5% hike, while in Suffolk Coastal the 3,600 affected families will hand over £78 more at the same rate.

In north-east Essex, meanwhile, affected families will pay an extra £199 – 43% above the average national rise – meaning they are paying 150% more than their county neighbours.

Sabrina Bushe, researcher at NPI, said: “Households that were previously deemed too poor to pay council tax will find hefty bills landing on their doormats.

“Hitting only the poorest and most vulnerable, this tax increase – which won’t raise much more money than it costs – is both unjust and unwise.”

Council tax benefit is being replaced by a new system – council tax support – and responsibility for it is being moved from central government to councils.

At the same time, the total spent on the benefit is being cut by 10% – and each council in England has had to decide whether to pass on the reduction to residents.

The study found 232 local authorities have devised schemes that will demand council tax from people regardless of income, while 58 will retain current levels of support for families.

Chris Goulden, head of poverty at JRF, said: “Making up the shortfall will be beyond most, with working hours under pressure and benefits falling behind inflation.

“This tax hike will push people into poverty or cause more hardship for already very poor households, taking money from families who had little to start with.”

Around 2.4 million low income families are expected to be affected following the changes, but pensioners are protected from the tax hikes.