start paying for registered or approved childcare.
get certification that your child is blind or their certification ends.
start or stop having a disability that puts you at a disadvantage in getting a job.
start or stop claiming benefits for yourself or a family member, or those benefits change.
have a baby or take responsibility for another child.
increase your working hours to 30 hours or more a week (combined if you’re in a couple with children).
have any change in income (report this immediately if it goes up or down by £2,500 or more).
Your tax credits are less likely to be affected, for example by building up an overpayment, if you tell HMRC as soon as you: If you estimated your income when you renewed your tax credits - for example because you’re self-employed - tell HMRC your actual income by 31 January. You could be fined up to £300 if you do not report certain changes within 1 month, and up to £3,000 if you give wrong information.
have been on strike for more than 10 consecutive days.
start working for less than 16 hours while claiming childcare costs - except in certain situations.
leave the UK permanently or lose the right to reside in the UK.
You must also tell HMRC straight away if you:
working hours fall below or go above the minimum required to qualify.
working hours fall below 30 hours a week (combined if you’re in a couple with children).
childcare provider is no longer registered or approved.
child over 16 leaves approved education or training, or a careers service.
child leaves home, for example moves out or goes into care.
childcare costs stop, go down by £10 or more a week, or you start getting help with them.
child stops going to childcare for 4 weeks or more when they would normally go.
child or partner dies (you do not need to tell HMRC if you’ve already used the Tell Us Once service).
living circumstances change, for example you start or stop a relationship, move in with a new partner, get married or form a civil partnership, permanently separate or divorce.