National Insurance UK Calculator

What is National Insurance?

National Insurance (NI) is a tax on earnings and profits paid by workers, employers, and self-employed people in the United Kingdom. NI contributions go toward funding the National Health Service, state pensions, unemployment benefits, and other social welfare programs.

To qualify for the full state pension, you typically need at least 35 years of NI contributions. The amount you pay depends on your employment status, income level, and the applicable tax year.

NI Classes

There are several classes of National Insurance:

• Class 1: Paid by employed earners based on weekly earnings above the Primary Threshold.
• Class 2: Paid by self-employed people at a flat weekly rate (abolished from 2024/25 for most, but voluntary contributions still possible).
• Class 4: Paid by self-employed people based on annual profits between the Lower Profits Limit and Upper Profits Limit.
• Class 3: Voluntary contributions to fill gaps in your NI record.

How NI is Calculated

For employed individuals (Class 1): You pay NI on earnings above the Primary Threshold (£12,570 for 2025/26). The main rate of 8% applies to earnings between the Primary Threshold and the Upper Earnings Limit (£50,270). Earnings above this limit are charged at 2%.

For self-employed individuals: From 2024/25, Class 2 NI was abolished (you receive contribution credits automatically if profits exceed the Small Profits Threshold). Class 4 NI is charged at 6% on profits between £12,570 and £50,270, and 2% on profits above £50,270.

How to Use the NI Calculator

• Enter your annual income or profits.
• Select the relevant tax year (2024/25 or 2025/26).
• Choose your employment type (employed or self-employed).
• The calculator will instantly show your NI contribution breakdown.