National Insurance, or NI, is a mandatory tax paid by UK salaried employees over 16 who earn more than £242 per week, or the self-employed who make a profit of £6,725 or more per year.

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About National Insurance

Introduced in 1911 and expanded after the war in 1948, National Insurance is a mandatory tax paid by most workers in the UK.

Some of the money raised this way is earmarked for state benefits for workers and their families, including state pensions.

The money is collected by HMRC, the UK tax authority, and for most people this happens automatically as the sums are deducted by employers as part of their payroll processes (PAYE).

Both employees and employers make an NI payment. Employees see this as a deduction from their gross salary, and it shows up as a separate line on their payslips. The self-employed must make their NI payments as part of their annual tax return.

Your National Insurance number

Everyone over the age of 16 in the UK is issued an unique National Insurance number by the Department of Work and Pensions. These contain two letters, six numbers and then a final letter.

<aside> ℹ️ If you have not received a National Insurance number, the UK Government website has a useful page


Further information

<aside> 🆘 If you’re struggling with your bills, our cost-of-living resources **page has the latest advice.


<aside> ℹ️ Which? provides some useful overview materials about National Insurance on their website, including an explanatory video


<aside> ℹ️ There are some useful National Insurance resources on the UK Government website

Overview of National Insurance

Check your national insurance record

Check your tax code for the current tax year


Last updated: November 2022

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