Tax credits claimants in Monmouthshire are being reminded to let HM Revenue and Customs (HMRC) know within one month of their childcare costs falling or ending.

Deliberately failing to let HMRC know when renewing a claim could constitute criminal fraud and result in prosecution.

Because tax credits are flexible, the amount claimants receive changes as their circumstances alter.

Changes to childcare that claimants need to tell HMRC about include:

•Average childcare costs changing by £10 or more a week.

•Their childcare provider stopping being approved or registered.

•Starting to receive childcare vouchers from an employer.

•Starting to get early learning or nursery education support.

Some 345,000 or 4.5 per cent of all tax credit awards in 2008/09 had errors relating to childcare.

The potential size of this loss to the Exchequer is £380m.