Nearly half of Universal Credit claimants in the UK are not receiving their full benefit payments because they are paying cash back to the Department of Work and Pensions.
Around 45% of all claims in February - 2.2million - had a deduction, meaning the claimant did not get their full entitlement that month.
Many were people who took out an advance from their own future benefits - to bridge the five-week wait for their first UC payment, The Mirror reports.
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Around 49% of all deductions, worth £86million in February alone, were to pay back an advance.
The DWP claim there is nothing wrong with this, because advances mean people are being paid the same amount of benefits over a longer time.
But campaigners say the five-week wait must be scrapped, because many skint Brits have no choice but to borrow against their own future benefits.
Another 16% of deductions (£28m) were to pay back historic Tax Credit overpayments - which MPs and campaigners have long said should be written off.
Deductions can also be taken for benefit overpayments, court fines or other debts.
SNP MP Chris Stephens, who obtained the data in Parliament, said: “This deductions policy is cutting holes in the safety net and pulling hundreds of thousands of people's incomes below subsistence levels.
“The only way this policy can be scrapped is if the five-week wait to receive a first payment is bridged with grants, rather than loans, and the advice of former ministers is heeded by writing off historic tax credit debt.”
Andrew Forsey, Director of Feeding Britain, added: “A workable proposal for bridging the five-week wait has been presented with cross-party support to ministers.
“We believe its introduction is now long overdue.
“A failure to do so will, sadly, add to the need for food banks.”
The maximum deduction was reduced to 25% of benefits in April after complaints that families were struggling with the system.
People also now have two years to pay back an advance, spreading their deductions more thinly over a longer time.
DWP minister Will Quince said: “We carefully balance our duty to the taxpayer to recover overpayments with our support for claimants.
“Safeguards are in place to ensure deductions are manageable.
“Customers can contact the Department if they are experiencing financial hardship in order to discuss a reduction in their rate of repayment, depending on financial circumstances.”
