Tax credits are worked on last years earnings so you should ring and ask advice not mentioning this years. It's down to family income. My husband works full time, until recently minimum wage plus comission, but we didn't qualify for childcare. I tried out various scenarios on their online calculator. We did qualify for the higher rate of tax credits this year as I asked to base it on predicted income this year. I think I predicted right but might yet get a bill to pay some back. Alot of my income has been via self employed work this year so tricky to plan for too. They have recently changed the thresholds though so definitely worth a phone call.