You can check your Child Benefit details, payments and payment dates through the official GOV.UK Child Benefit online service, using your Government Gateway sign-in. HMRC may also send a decision letter once your claim has been processed, so check your post and online account. If you cannot see an update or need to ask about a delayed claim, contact the Child Benefit Office on 0300 200 3100. Have your National Insurance number and claim details ready, and check GOV.UK for the latest contact information and opening hours.