National Insurance Calculator

Work out how much Class 1 National Insurance you'll pay as an employee, or Class 4 National Insurance if you're self-employed, for the 2026/27 tax year.

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£1,334 Class 1 National Insurance per year

That's £111.20 per month — 3.8% of your income.

FigureAmount
Income£35,000.00
National Insurance threshold£12,570.00
National Insurance due£1,334.40

Based on the 2026/27 Class 1 thresholds: 8% between the Primary Threshold and Upper Earnings Limit, 2% above it. Estimates only, not financial advice.

How National Insurance is calculated

National Insurance is calculated separately from Income Tax, directly on your gross earnings above a threshold — it isn't reduced by your Personal Allowance. Employees pay Class 1 NI on pay above the Primary Threshold; self-employed people pay Class 4 NI on profits above a similar lower limit. Both use a main rate up to an upper limit, then a lower rate above it. See our full Take-Home Pay Calculator to combine National Insurance with Income Tax and student loan repayments.

Frequently asked questions

What is National Insurance?

National Insurance is a UK tax on earnings that counts towards your entitlement to certain state benefits and the State Pension. Employees pay Class 1 NI; self-employed people pay Class 4 NI on their profits.

What's the difference between Class 1 and Class 4 NI?

Class 1 National Insurance is paid by employees on gross pay above the Primary Threshold, deducted automatically through payroll. Class 4 National Insurance is paid by self-employed people on annual profits above a lower limit, usually via Self Assessment.

Do I pay National Insurance on all my income?

No. You only pay National Insurance on earnings above a threshold. Above that threshold, a main rate applies up to an upper limit, and a lower rate applies to everything above it.