National Insurance Number

Your National Insurance (NI) number is a nine-character identifier (two letters, six digits, one letter) issued by HMRC and the Department for Work and Pensions. It tracks your NI contributions, which build entitlement to the State Pension (you need 35 qualifying years for the full new State Pension), statutory sick pay, maternity pay, and contribution-based benefits. UK residents are typically allocated one before their 16th birthday. Employers use it to report PAYE earnings, and you provide it when opening a workplace pension, claiming benefits, or filing Self Assessment.