How do we get a national insurance number?

register with them!

I presume that your wife was not born in the UK and has never worked in the UK. If so she will not yet have a National Insurance number. She will therefore not be able to accumulate a government pension, nor will she be able to claim some benefits on her own. If she wants a National Insurance number then she will have to get paid employment or become self-employed and register with the HMRC (Her Majesty's Revenue and Customs) ie. the tax man! As soon as you have an income then the Government will give you a National Insurance number.... because they want to make sure you pay (appropriate levels of) tax. If your wife gets a job then your wife will get a National Insurance number via the employer... until then she has no reason to need one... and even if you write a letter to Tony Blair.... they wouldn't give her one! As an example; my wife is from Taiwan, we have been in the UK for 2+ years, she is self-employed and teaches Chinese.... as soon as she registered as self employed with the HMRC she got a National Insurance number via the HMRC / DWP. Basically, get a job even if it's at Tesco's stacking shelves.... which I've done before. As far as Tax Credits go....just call them and tell them your situation. They will just send you some forms and will then deposit a large amount of money in your bank account before demanding it back next year... (I joke). You cannot claim for more than 3 months in arrears so you only need your last years P45...or is it P60...I forget. Whatever shows your earnings last year. Go to it fella' go get your tax credits....it's your money that they want to pay back to you...stupid system ...really!!!

All british citizens should have an N.I number from the age of 16, As far as tax credits go you might aswell applie they seem to be giving tax payers money out to anyone these days.