The basics
National Insurance is a tax on earnings that builds your entitlement to certain benefits, including the State Pension. Employees, the self-employed and employers all pay different classes.
Why it matters
Your NI record determines your State Pension. Gaps can sometimes be filled with voluntary contributions — worth checking before retirement.
Frequently asked questions
What are the current rates?+
NI rates and thresholds change — check the latest on GOV.UK. The take-home pay calculator estimates the employee portion.