Here are the requirements that are needed to prove your National Insurance number:
- P45 or P60
- A letter from HM Revenue and Custom in which tax or tax credit is mentioned
- Bank statements should be available which show the direct payment through a debit card. The payment has to be made for class-2 National Insurance contributions. Bank statements can also include the benefit payments and your NI number should be printed on the statement.
- Payslips, salary statements, work pension statement
- National Insurance number card which should not be handwritten
- Letter sent by a Pension Service or Jobcenter Plus
- Universal tax credits letter
- Job seekers allowance letter