Self-employed people in the UK pay two types of National Insurance: Class 2 and Class 4. Both are paid through Self Assessment. Class 2 NI builds your State Pension entitlement; Class 4 NI contributes to the NHS. Neither entitles you to Job Seekers' Allowance.
Class 2 National Insurance
Class 2 NI changed significantly in 2024. From the 2024/25 tax year, you no longer pay a separate Class 2 NI charge. However, if your profits are above the Small Profits Threshold (£6,725), you automatically receive Class 2 NI credits as part of your Self Assessment. This preserves your State Pension entitlement at no extra cost.
If your profits are below £6,725, you can pay Class 2 NI voluntarily at £3.45 per week (2025/26) to protect your State Pension record.
Class 4 National Insurance
Class 4 NI is calculated as a percentage of your taxable business profits above the lower profits limit.
| Profit band (2025/26) | Class 4 NI rate |
|---|---|
| Below £12,570 | 0% |
| £12,570 to £50,270 | 6% |
| Above £50,270 | 2% |
How to pay Class 4 NI
Class 4 NI is calculated automatically when you complete your Self Assessment return. You do not need to calculate or pay it separately. It is included in your total January and July tax payments alongside Income Tax.
Does NI count towards State Pension?
You need 35 qualifying years of NI contributions to receive the full new State Pension (£221.20 per week in 2025/26). A qualifying year requires contributions at or above the Class 2 threshold. Check your NI record through your Personal Tax Account on GOV.UK.
Gaps in your NI record
If you have gaps in your NI record, you may be able to pay voluntary Class 3 NI contributions (£17.45 per week in 2025/26) to fill them. This is usually worth doing if you are within 15 years of State Pension age. Use HMRC's online checker to assess whether topping up makes sense for you.
If your profits are between £6,725 and £12,570, you receive NI credits towards your State Pension even though you pay no Class 4 NI. This is an important protection for lower-earning self-employed people.
This guide provides general information only and does not constitute financial, tax, or legal advice. For your specific situation, consult a qualified accountant. Find one via our accountant directory.