UK National Insurance Calculator

Free online NI calculator for 2025/26 tax year. Calculate employee, employer and self-employed National Insurance contributions instantly.

Calculate Your National Insurance

What is National Insurance?

National Insurance (NI) is a tax on earnings and profits paid by employees, employers and self-employed people in the United Kingdom. NI contributions build your entitlement to certain state benefits and the State Pension. Unlike Income Tax, NI is not a cumulative tax on your total income. It is calculated per pay period (weekly or monthly) based on your earnings above specific thresholds.

Your NI record determines eligibility for the State Pension, Contributory Employment and Support Allowance, Jobseeker's Allowance, Maternity Allowance and Bereavement Support Payment. Most people need at least 35 qualifying years of NI contributions to receive the full new State Pension.

NI Letter Categories Explained

Your NI category letter determines the rate of National Insurance you pay. Most employees are in Category A. The table below shows the main categories and their rates for 2025/26.

CategoryWho it applies toEmployee rateEmployer rate
AStandard employees (most workers)8% / 2%13.8%
BMarried women or widows with reduced rate election1.85%13.8%
CEmployees over State Pension age0% (exempt)13.8%
HApprentices under 258% / 2%0% (on earnings up to GBP 50,270)
JEmployees who can defer NI2%13.8%
MEmployees under 218% / 2%0% (on earnings up to GBP 50,270)
ZEmployees under 21 who can defer2%0% (on earnings up to GBP 50,270)

Note: Class 1A employer NI at 13.8% also applies on most benefits in kind (company cars, private health insurance). The rates shown are for the 2025/26 tax year and are subject to change in the annual Budget.

What Your National Insurance Pays For

State Pension

The new State Pension (GBP 221.20 per week in 2025/26) is the largest benefit funded by NI. You need at least 10 qualifying years for any State Pension and 35 years for the full amount.

New Style Jobseeker's Allowance

If you have paid enough NI contributions in the last 2 to 3 tax years, you may qualify for contribution-based JSA paid at up to GBP 90.50 per week for up to 6 months.

New Style Employment and Support Allowance

ESA provides financial support if you cannot work due to illness or disability. Contribution-based ESA is paid at up to GBP 90.50 per week (assessment phase) based on your NI record.

Maternity Allowance

Mothers who have paid enough NI can claim Maternity Allowance of up to GBP 184.03 per week for 39 weeks. You need 26 weeks of NI contributions in the test period.

Bereavement Support Payment

A tax-free lump sum and monthly payments for widows, widowers and surviving civil partners whose spouse or civil partner paid NI contributions. Up to GBP 3,500 lump sum plus 18 monthly payments.

NHS and Other Public Services

NI contributions help fund the NHS, although most NHS funding comes from general taxation. NI also contributes to the National Insurance Fund which pays for contributory benefits.

NI Thresholds for 2025/26

ThresholdAnnual amountWeekly amountMonthly amount
Primary Threshold (employee NI starts)GBP 12,570GBP 242GBP 1,048
Upper Earnings Limit (higher rate kicks in)GBP 50,270GBP 967GBP 4,189
Secondary Threshold (employer NI starts)GBP 9,100GBP 175GBP 758
Lower Profits Limit (self-employed Class 4 starts)GBP 12,570GBP 242GBP 1,048
Upper Profits Limit (self-employed Class 4 higher rate)GBP 50,270GBP 967GBP 4,189
Small Profits Threshold (Class 2)GBP 6,725GBP 129GBP 560

Self-Employed NI (Class 2 and Class 4)

If you are self-employed, you pay National Insurance differently. Class 2 NI contributions are a flat weekly amount (GBP 3.45 per week in 2025/26) if your profits exceed the Small Profits Threshold of GBP 6,725 per year. Class 2 contributions count towards your State Pension and other contributory benefits.

Class 4 NI is based on your annual profits. You pay 6% on profits between GBP 12,570 and GBP 50,270, and 2% on profits above GBP 50,270. Class 4 does not count towards benefit entitlement; it is an additional contribution on your trading profits.

Note that from April 2024, the government reformed Class 2 so most self-employed people with profits above the Small Profits Threshold get a deemed Class 2 contribution treated as paid without actually needing to pay it. Those with profits between the Small Profits Threshold and the Lower Profits Limit can opt to pay Class 2 voluntarily to protect benefit entitlement.

Disclaimer: This calculator provides estimates for illustrative purposes only. National Insurance rates, thresholds and rules change annually and may vary depending on your individual circumstances. The calculations shown do not constitute financial or legal advice. Always consult a qualified accountant or HMRC for accurate advice about your NI contributions. While we strive for accuracy, we accept no liability for errors or omissions. For official information, visit GOV.UK National Insurance.