Why do you call for to state your National Insurance on UK Visitor application.?

I worked in the UK and returned back home. Now after two yrs I would resembling to visit uk on a holiday. I recently notice now on UK visitor application form you have need of to state your National Insurance number if you have worked in the UK previously. Why is this?. I don't even remember my NI number.
"> When you worked within Britain one of the deductions from your wage was for National Insurance. This go towards medical treatment on the NHS, state pension etc. To get your NI no. contact the DHSS (Department of Health and Social Security.)

http://www.gov.im/dhss/security/payments…

Hope this help. Enjoy your holiday. I hope you get better weather than it is just presently. Its sleety snow.
Because they need to make sure you do not owe any rear legs taxes. Unfortunately too many people work surrounded by the UK then leave in need paying taxes. This way they can check and will probably make you pay envelope up before you would be allowed into the country again


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