Get a National Insurance number for a looked after child

How to get a National Insurance number for a child who is being looked after by a local authority.


Children who are looked after by local authorities do not automatically get a National Insurance number.

If you’re a child’s social worker, you should write to HMRC to apply for a National insurance number on the child’s behalf.

How to apply

You should apply:

  • after a child is 15 years and 9 months
  • in writing, to HMRC using your local authority’s official letter-headed paper

The letter must include:

  • a statement that you’re a social worker applying for a National Insurance number for a looked after child
  • the child’s full name
  • any previous names the child has used
  • the child’s date of birth
  • the date the child went into care
  • the child’s current residential address
  • the contact details of the social worker who has written the letter

If the child is a British citizen, the letter should also include:

  • any previous addresses (such as their parent’s old address or the child’s last address before they were taken into care)
  • a photocopy of either:
    • the child’s birth certificate
    • their Care Order
    • the ID page of the child’s passport

If the child is an unaccompanied minor and supported by the Home Office, you must include photocopies of either:

  • the child’s Home Office documents
  • both sides of a residence permit

The letter and photocopies of any documents should be posted or faxed to:

PT Operations North East England
HM Revenue and Customs

Fax: 0191 213 1262

You must send a separate letter for each National Insurance number application you make.

What happens next

HMRC will send a letter to the child confirming their National Insurance number.

If more information is needed we will issue a CA3530 ‘Application for a National Insurance number for a child looked after by a local authority’ to confirm the details needed.

Published 18 August 2014
Last updated 2 November 2018 + show all updates
  1. The address to write to for applications for a National Insurance number for a looked after child has been updated.
  2. First published.