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I forgot my sofi number. Where can I find it?


I got a sofi number from back in 2006 when in I was in the Netherlands. Unfortunately I don‘t have access to the sofinumber anymore. How do I find out what my (new or old) sofi number is/was?


If you have lost your sofinumber (or BSN) there are some options to retrieve it:

  1. If you have a Dutch passport, identity card or driving license you can find it there. The number is also stated on salary slips which you received from an employer and on correspondence from the tax authorities. 
  2. If you are registered with the municipality you can also go the town hall and ask them if they can find your sofi number.
  3. Go to an office of the Dutch tax authorities and ask them if they can see your sofinumber. 

But I have left the Netherlands and don‘t have Dutch identity papers...

If you left the Netherlands and deregistered you will of course not be registered with the municipality anymore. But the sofinumber will remain valid and is not given to somebody else.

The best option would be to check all the documents you do have whether it contains a tax number. The tax number consists of 9 digits (

You can also write a letter to the tax authorities foreign department in Heerlen and request them to let you know what your sofinumber is. Don‘t forget to include a copy of your passport so that they can identify you. On top of that I would also suggest to include a copy of a statement from your local municipality in which they confirm your current address. The more information the better. But the tax authorities can (still) refuse your request due to "security reasons" since you don‘t show up in front of them in person. So sending a written request is not a guarantee that you will get the sofinumber. In that case the only option would be to come to the Netherlands and visit one of the offices of the tax authorities. 

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Comments (3)
Comment by Modestas on Fri, Oct 17th, 2014 at 11:34 AM
I forget sofi number, and forget document in other country
Comment by JOHANNES RUTSKER PIETER van der DUIM on Wed, Aug 31st, 2016 at 2:39 PM
Could you please tell me the location of my sofinumber on my passport please.
Comment by Arjan Enneman on Wed, Aug 31st, 2016 at 6:56 PM
You can find the sofinumber behind your date of birth on the passport. It is also called "persoonsnummer". If you google on "sofinummer paspoort" then you will find several example images.
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