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CA5403 - Your National Insurance number

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Form URL
 CA5403
Description

How to get written confirmation of your National Insurance number if you can't find it.
The online version of this form has been temporarily withdrawn.

You can complete the form on screen, print it, and post it to HM Revenue and Customs (HMRC).

If you have problems opening the form, find help by following the link below 'Get help viewing PDFs' or use this version of CA5403. You'll have to print this version and fill it in by hand.

Whichever version you choose please read the factsheet first. You'll find it under 'Help and guidance relating to this form' in the next section.

How to get written confirmation of your National Insurance number if you can't find it

Help and guidance relating to this form

Form URL
Applying for a National Insurance number
How to get a National Insurance number, when you'll need one, what to do if you don't receive it or forget or lose it

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