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National Insurance: What You’re Actually Paying For

It’s not insurance and it’s not a pension fund — but it affects both

What Does NI Fund?

National Insurance was originally designed to fund the State Pension, NHS, and unemployment benefits. In practice, it’s basically a second income tax with a confusing name. Your NI record determines your State Pension entitlement.

Employee NI Rates (Class 1)

EarningsRate
Below £12,570/year0% (but you get credits from £6,396)
£12,570 – £50,2708%
Over £50,2702%

Employer NI

Your employer also pays NI on your behalf — 13.8% on earnings above £9,100. This is invisible to you but it’s a real cost of employing you. It’s why employers love salary sacrifice: it reduces NI for both parties.

Key Concept

Your “true” tax rate on employment income between £12,570 and £50,270 is actually 28% (20% income tax + 8% NI). On £50,271–£125,140, it’s 42% (40% tax + 2% NI). Add employer NI and the total cost of paying you is even higher.

NI Classes Explained

ClassWho PaysPurpose
Class 1Employees (via PAYE)State Pension, benefits
Class 2Self-employed (flat rate)State Pension qualification
Class 3Voluntary contributionsFill gaps in NI record
Class 4Self-employed (on profits)Percentage of profits

NI Credits

You can get NI credits (counted as if you paid contributions) if you’re:

  • Claiming Child Benefit for a child under 12
  • Claiming Jobseeker’s Allowance or Universal Credit
  • Caring for someone for 20+ hours per week
  • On statutory sick, maternity, or paternity pay

State Pension: 35 Years

You need 35 qualifying years of NI to get the full State Pension (£221.20/week in 2024/25). You need at least 10 years to get anything at all. Check your record at gov.uk/check-national-insurance-record.

Real-World Example

If you have gaps in your NI record, you can buy voluntary Class 3 contributions at £17.45/week. Each year you buy adds roughly £329 per year to your State Pension for life. That’s a £907 investment that pays back every single year — one of the best “investments” available.

Self-Employed NI

If you’re self-employed, you pay:

  • Class 2: £3.45/week (flat rate) if profits are over £12,570
  • Class 4: 6% on profits between £12,570 and £50,270, then 2% above that

Warning

NI rates change frequently. The rates here are based on 2024/25. Always check the latest figures at gov.uk/national-insurance-rates-letters.