HM Revenue & Customs

National Insurance number

You can find the National Insurance number on documents sent to the deceased from HM Revenue & Customs or Department for Work & Pensions. It is a mixture of letters and numbers in the format AB123456C or ab123456c. Do not use spaces when entering this number.

Where the deceased did not have a National Insurance number (usually people with a non-UK domicile) you will need to follow the link below to submit form IHT422 on the GOV.UK website and you will not be able to use this online service.

Inheritance Tax forms