National Insurance Explained UK

National Insurance Explained UK

National Insurance (NI) is a tax on earnings that funds key UK state benefits, including the State Pension, statutory sick pay, and maternity allowances. Whether you are employed, self-employed, or not working, understanding how NI works helps you protect your future entitlements and avoid overpaying.

What Is National Insurance?

National Insurance is a UK tax system introduced in 1948 as part of the post-war welfare state. Unlike income tax, which applies to most forms of income, NI is specifically tied to employment earnings and profits. Its primary purpose is to fund:

The State Pension (the new flat-rate pension, currently up to £11,973 per year for 2025/26)
Statutory Sick Pay (SSP) and Statutory Maternity Pay (SMP)
Jobseeker’s Allowance (JSA) and Employment and Support Allowance (ESA)
The NHS (partially)

For example, a teacher earning £30,000 annually pays Class 1 NI through PAYE (Pay As You Earn). These contributions build up their NI record, which determines their eligibility for the State Pension at retirement. To receive the full new State Pension, you need 35 qualifying years of NI contributions; a minimum of 10 years is required for any payment.

National Insurance Rates for 2025/26

Employee Class 1 Contributions

For the 2025/26 tax year, employees pay NI as follows:

Earnings (Annual)	Earnings (Weekly)	NI Rate
Up to £12,570	Up to £242	0% (Primary Threshold)
£12,571 to £50,270	£242 to £967	8% (main rate)
Above £50,270	Above £967	2% (Upper Earnings Limit)

Example: Someone earning £40,000 per year pays 8% on £27,430 (£40,000 minus £12,570) = approximately £2,194 per year (about £183 per month).

These rates reflect significant cuts: the main employee rate was 12% before January 2024, reduced to 10% in January 2024, then further cut to 8% in April 2024. Source: GOV.UK — National Insurance rates and thresholds.

Employer Contributions

Employers pay Class 1 employer NI at 15% on all employee earnings above £5,000 per year (the Secondary Threshold, reduced from £9,100 from April 2025).

Example: For an employee earning £25,000, the employer pays 15% on £20,000 (£25,000 minus £5,000) = £3,000 per year.

Source: GOV.UK — Employer National Insurance.

Self-Employed Contributions (Class 4)

Profits (Annual)	NI Rate
Up to £12,570	0% (Small Profits Threshold)
£12,571 to £50,270	6% (main rate)
Above £50,270	2%

Example: A self-employed graphic designer with £30,000 in annual profits pays 6% on £17,430 (£30,000 minus £12,570) = approximately £1,046 per year.

Note: Class 2 NI was abolished from 6 April 2024. Self-employed individuals no longer pay the flat-rate weekly contribution. They now build NI records through Class 4 contributions alone, with access to the State Pension and contributory benefits maintained. Source: GOV.UK — Class 2 abolition.

Types of National Insurance Classes

Class 1 — Paid by employees and employers. Employees pay 8% on earnings between £12,570 and £50,270 (2% above). Employers pay 15% above £5,000. This is the most common NI class, deducted automatically through PAYE.
Class 1A/1B — Paid by employers on certain non-cash benefits, such as company cars or private health insurance. These do not affect the employee directly but are part of the employer’s overall NI liability.
Class 2 (abolished April 2024) — Previously a flat-rate weekly contribution for self-employed individuals. Its abolition simplified self-employed NI without reducing State Pension entitlement. Source: GOV.UK.
Class 4 — Paid by self-employed individuals based on profits. For 2025/26, the rate is 6% on profits between £12,570 and £50,270, and 2% above. This was reduced from 9% in April 2024.
Class 3 — Voluntary contributions to fill gaps in your NI record. For 2025/26, the rate is £17.45 per week (£907.40 per year). Useful for those with career breaks, such as parents or people who lived abroad.

How to Check Your NI Record

Your NI record tracks contributions and credits over your working life. You can check it free on GOV.UK — Check your National Insurance record. You will need your Government Gateway user ID.

Common reasons for gaps include:

Career breaks for childcare or caring responsibilities
Periods living or working abroad
Low earnings below the threshold
Self-employment with low profits

If you have gaps, you may be able to make voluntary Class 3 contributions to fill them. There is currently a special deadline extension allowing people to fill gaps going back to 2006 until 5 April 2025 (after which the standard 6-year limit applies). Source: GOV.UK — Voluntary NI contributions.

National Insurance and the State Pension

Your NI record directly determines your State Pension. The new State Pension (for those reaching State Pension age after 6 April 2016) requires:

10 qualifying years minimum for any payment
35 qualifying years for the full amount (£11,973 per year for 2025/26)

You earn a qualifying year by paying NI contributions or receiving NI credits. Credits are available for:

Claimants of Carer’s Allowance, Jobseeker’s Allowance, or ESA
Parents receiving Child Benefit for a child under 12
People on approved training courses

Source: GOV.UK — State Pension.

What Most People Miss

Most guides cover the basics, but several lesser-known details matter:

NI stops at State Pension age. Once you reach State Pension age (currently 66), you no longer pay Class 1 or Class 4 NI, even if you continue working. Ask your employer for a Certificate of Age Exception from HMRC.
Carer and parent credits are automatic but you must claim Child Benefit to trigger them — many higher-rate taxpayers skip claiming and lose credits.
Voluntary contributions can be extremely good value. Paying £907 per year (Class 3) to fill a gap can add over £328 per year to your State Pension — a 36% return for life.
NI doesn’t fund the NHS as widely believed. While the NHS receives some NI funding, the vast majority of its budget comes from general taxation.

FAQ

“What is National Insurance in the UK?” | “National Insurance is a tax on earnings that funds state benefits including the State Pension, statutory sick pay, and maternity pay. It is deducted automatically from wages (employees) or paid through Self Assessment (self-employed).” “How much National Insurance do I pay in 2025/26?” | “For 2025/26, employees pay 8% on earnings between £12,570 and £50,270, and 2% above £50,270. Self-employed individuals pay 6% on profits between £12,570 and £50,270, and 2% above.” “When did Class 2 National Insurance end?” | “Class 2 NI was abolished from 6 April 2024. Self-employed individuals now pay only Class 4 NI, and their State Pension entitlement is protected through Class 4 contributions alone.” “How do I check my National Insurance record?” | “You can check your NI record free on GOV.UK using your Government Gateway ID. The record shows your contribution history and any gaps that may affect your State Pension.” “What is the employer National Insurance rate for 2025/26?” | “Employers pay 15% on all employee earnings above £5,000 per year for 2025/26. The Secondary Threshold was reduced from £9,100 to £5,000 from April 2025.”

Conclusion

National Insurance is a cornerstone of the UK welfare system. Key points for 2025/26:

Employees pay 8% on £12,570–£50,270, then 2% above
Self-employed pay 6% on profits of £12,570–£50,270 (Class 2 abolished)
Employers pay 15% above £5,000
You need 35 qualifying years for the full State Pension
Check your record on GOV.UK and fill gaps early

For tailored advice, consult a qualified financial advisor or contact HMRC directly via GOV.UK.