Multiple NI Numbers

Hi All - not sure if this is the right place to post this, but it seems like a good place to start.

It seems I have been assigned a total of THREE natioanl insurance numbers.  If I understand things correctly, one of the numbers was assigned by the Expat office in Wales (starts with a 6), one was assigned by the HMRC when I filed (ver late) my 03-04 UK taxes (starts with a 1), and one I receved when I applied for a NI number (not knowing I already had one, or two as it may be) when I changed jobs and started getting paid in the UK (starts with an S). 

I have spoked to the HMRC several times both in Wales and at their main office and I was told that the correct number is the one that starts with an "S".  They continue to tell me that it is going to get fixed, but I still receive documents with the wrong number on them, and the HMRC website still lists my NI number as the one starting with the "1".  I have used the "S" number when filing my return and this is the one I have given to my employer.  Also, it appears that I only have one UTR number, which is good I think.

My question is, how aggressively should I be persuing this?  Is it one of those things where I should just keep calling them every 6 months or so to find out if it has been resolved, or should I take a more agggressive approach?

Thanks in advance

Your NI number should have the following format

AB123456C

the "numbers" you mention that start with numbers rather than letters are not your
NI number.

If you file a UK self-assesement return, then you have an NI number and a UTR, an Unique Taxpayer Reference.  UTRs start with numbers and have no letters in them.   It is possible that you're mixing the two up? 

Lizzit,

I know my UTR number - it is 9 digits and all numbers.

According to Inland Revenue, the two NI numbers that I have that start with numbers (but also contain letters) are "temporary" numebrs that should be replaced by my permanent number, which follows the format that Nun suggests.  But on the self assesment site, the number listed as my NI number is still one of the temporary numbers, and is listed as, for example, 12A33445.

I just want to make sure that I avoid any potential problems down the road.

Thanks

I think Lizzit may be confused here.

The temporary NI numbers are computer generated by HMRC but can be ignored entirely.  The only valid number is the one on your NI card.

There is no need for you to bother HMRC to fix this at all as it has no effect on your tax or benefit position.  If HMRC want to muddle themselves up then let them!