Adult British subjects must have a National Insurance (NI) number as it is very difficult to live outside of the system of paid employment and state benefits. An NI number is unique and allows the government to keep a record of payments and entitlements. Its format is XY 12 34 56 Z. It is requested by government departments, employers and financial institutions, including the student loan companies.
The National Insurance Act of 1911 introduced NI numbers and for many decades people were required to buy NI stamps to stick on a record card. This is where the phrase to ‘get your cards’ comes from, meaning that you are fired! Youngsters receive their numbers when they are aged 15 years and 9 months and they must take care to keep them confidential for the rest of their lives to avoid identity fraud by unscrupulous fiends.
If you lose your NI number there is a government helpline but you will never be told the number over the phone for security reasons. Instead, it will be posted to your address within fifteen days. Foreigners wishing to move to the UK must apply for a number, which may involve attending an interview at a Jobcentre Plus.
(Image of 1940 NI card: Wikimedia Commons / Public domain)