If claimants miss the 31st July deadline their payments might stop, according to HM Revenue and Customs (HMRC).

Nick Lodge, director general of benefits and credits, said: “We are asking claimants to renew immediately. The sooner they do, the sooner we can check their payments and avoid paying too little, or too much money, which they then have to pay back.”

Tax credits renewal packs have been sent to about 5.8 million people since April. Last year more than 80% of claimants renewed by the 31 July deadline.

Claimants must check the accuracy of the information in their packs, and tell officials about any changes to circumstances that they haven’t already reported.

These include altered working hours, childcare costs or pay. They must also tell HMRC whether they are single or living with a partner.

Claimants can renew by calling the Tax Credits helpline – 0345 300 3900, or post their renewal to the address in the pack that was sent to them.