The chief executive of HM Revenue and Customs has warned parents to not leave registering for child benefits "until the last minute", on the eve of the stated deadline.
Lin Homer told BBC Radio 5 Live:
We think there are about 200,000 people who need to get off their backsides and do something.
HMRC is committed to helping people pay the right amount of tax and urges parents who have been affected by the changes to child benefit to register for self-assessment.
We know that lots of people leave it until the last minute.
More top news
A woman died during scenes of panic at a Kenyan university after police carried out a terror drill without the students being told first.
The Prince of Wales said world companies 'pay no attention' to the damage their supply chains cause to forests.
Investigators say a faulty rudder system and the pilots' responses contributed to an AirAsia jet crash last year which killed 162 people.