Working Tax Credit is paid to single low earners with or without children who are aged 25 or over and are working over 30 hours per week and also to couples without children, at least one of whom is over 25, provided that at least one of them is working for 30 hours a week. If the claimant has children they could claim Working Tax Credit from age 16 upward provided that they are working at least sixteen hours per week. It is being replaced by Universal Credit.