Applying for a National Insurance number

Working or claiming benefits in the UK? You may need to apply for a National Insurance number first. If you do not already have one, your NI number is essential for tracking tax, National Insurance contributions and accessing certain government services. While most UK residents receive their number at age 16, newcomers or those starting work later in life may need to apply. It takes around four weeks to process after proving your identity, but you can still start work or claim some benefits while you wait.

According to HMRC guidance, you can apply for a National Insurance number if you:

  • live in the UK,
  • have the legal right to work in the UK, and
  • are working, looking for work, or have a job offer.

You can still start work without an NI number, as long as you can prove your right to work in the UK. Similarly, you can apply for benefits or a student loan without an NI number, though you may be asked to provide one later if required.

Most teenagers living in the UK receive a letter shortly before their 16th birthday confirming their NI number. This letter is important and should be kept safe. Your NI number is unique and stays the same for life, even if your name, address or nationality changes. If you lose your NI number, you can find it on official documents like payslips, P60s or via your personal tax account.

Source:HM Revenue & Customs | 14-07-2025
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