A quarter of women do not earn enough to benefit from the latest rise in the income tax personal allowance, the TUC said yesterday.

The TUC said the government’s policy of raising the amount someone can earn before they start to pay income tax was “expensive and poorly targeted.”

The allowance goes up from £9,440 to £10,000 this month, but it is not enough to help low-paid workers or parents on low to middle incomes, said a congress report.

It cited recent analysis by the Institute for Fiscal Studies which revealed that rich families gained the most from the policy, while the poorest gained the least.

The TUC highlighted that raising personal allowances from £6,475 in 2010/11 to £10,000 has cost the Treasury over £10 billion, but it has done nothing to help the four million lowest-paid workers, said.

About one in six British workers do not earn enough to benefit at all from the new rise and a further 333,000, mainly women, employees will only partially benefit, the research found.

TUC general secretary Frances O’Grady said: “It is odd to see politicians fighting to take the credit for a policy that does so little to help hard-working families and one which is also particularly bad at helping women.”

The report also showed that raising the personal allowance is failing to help working families on low to middle incomes in receipt of universal credit.

The TUC is concerned that because working families’ entitlement to universal credit is based on their post-tax income, for many two-thirds of any financial gain from the personal allowance will be taken away through reductions to universal credit.

Ms Grady said: “It is frustrating to see families on low to middle incomes losing out from the personal allowance rise because the policy comes into direct conflict with universal credit.

“If the government really wanted to help hard-working families on low to middle incomes it should abandon further rises in the personal allowance and focus instead on reversing damaging cuts to tax credits and universal credit that will leave millions of families worse off.”

Congress is urging the government to stop penalising families receiving universal credit by increasing the “work allowance” — the point at which families’ entitlement to universal credit starts to fall — in line with any further rises in the personal allowance.