Nearly 100,000 families in Birmingham will be hit by tough government plans to freeze benefits for four years, currently being debated in Parliament.
Charity the Children’s Society said it would lead to more children living in poverty, as family incomes fail to keep up with rising costs.
A study by the charity found that 211,700 children living in 99,000 households in Birmingham will be affected.
And in the West Midlands county, including Birmingham, Solihull, Coventry and the Black Country, 466,000 children in 230,000 households will be affected by benefit freezes.
Work and Pensions Secretary Iain Duncan Smith says bringing welfare spending under control is fairer for everybody and encourages more people to work.
MPs have been debating the Welfare Reform and Work Bill, which includes a range of tough measures such as:
Freezing benefits for four years
Cutting the benefit cap - the maximum that most families can claim in benefits - from £26,000 to £20,000 a year outside London
Limiting Child Tax Credits, a benefit to help pay for the cost of raising a child, to a family’s first two children
Benefits to be frozen include the main rates of income support , Jobseeker’s Allowance, employment and support allowance, housing benefit and universal credit.
If MPs back the plans, as expected, the freeze will begin in April this year.
Matthew Reed, chief executive of The Children’s Society, said: “Austerity has hit families hard, including those in work. Further cuts to support would push more children into poverty and undermine incentives for families to move into work or earn more.”
But the Government says it was unfair that benefits had risen faster than wages.
Average pay packets have risen by 12 per cent since 2008 but many benefits such as Jobseeker’s Allowance have risen by 21 per cent.
And working families will see their earnings increase for the four years that the freeze is in place, with average annual earnings growth expected to reach around 3.9 per cent by 2020, according to the Government.
The Government is increasing the income tax personal allowance threshold to £12,500 by 2020 – effectively cutting income tax for many working people – and introducing a 50p “living wage” increase to the minimum wage, pushing up the minimum wage to £9 per house for workers over 25.
A Department for Work and Pensions spokesman said: “The reality is that our welfare reforms are incentivising work while protecting the most vulnerable, and ensuring we have a system which is fair to those who pay for it, and to those who benefit from it.
“We are bringing welfare spending under control, while, crucially, helping people into work and through Universal Credit helping them to earn more.”