National Insurance Contributions Calculator UK 2025/26
Calculate exactly how much National Insurance you owe as an employee or self-employed person — with employer NI costs and State Pension qualifying year guidance.
National Insurance Calculator 2025/26
Your NI Estimate
This estimate is for guidance only. For official calculations, use the HMRC Basic PAYE Tools or consult a qualified accountant.
What Is National Insurance?
National Insurance (NI) is a compulsory tax paid by employees, employers and the self-employed in the United Kingdom. Contributions go into the National Insurance Fund, which funds key state benefits including the State Pension, statutory sick pay, maternity pay, and jobseeker’s allowance. Unlike income tax, NI is hypothecated — it is theoretically earmarked for specific social security purposes, though in practice the Treasury manages the funds collectively.
National Insurance contributions build up your entitlement to contributory state benefits. The most significant of these is the State Pension: to receive the full new State Pension of £221.20 per week in 2025/26, you need 35 qualifying years of contributions or NI credits. A minimum of 10 qualifying years is needed to receive any State Pension.
Class 1: Employee National Insurance 2025/26
Employees pay Class 1 National Insurance contributions through the PAYE system, deducted automatically from wages before they are paid. The rates for 2025/26 are:
| Earnings Band (Annual) | NI Rate | Notes |
|---|---|---|
| Up to £12,570 (Primary Threshold) | 0% | No employee NI payable |
| £12,571 to £50,270 (Upper Earnings Limit) | 8% | Main rate — cut from 10% in Jan 2024, then 8% from April 2024 |
| Above £50,270 | 2% | Additional rate (unchanged) |
For a straightforward example, an employee earning £40,000 in 2025/26 pays:
- 0% on the first £12,570 = £0
- 8% on the remaining £27,430 (£40,000 − £12,570) = £2,194.40
- Total annual employee NI: £2,194.40 (£182.87/month)
For a higher earner on £70,000:
- 0% on first £12,570 = £0
- 8% on £37,700 (£50,270 − £12,570) = £3,016.00
- 2% on £19,730 (£70,000 − £50,270) = £394.60
- Total annual employee NI: £3,410.60 (£284.22/month)
Employer National Insurance (Secondary Contributions) 2025/26
Employers pay secondary Class 1 NI contributions on earnings above the Secondary Threshold. From April 2025, the government introduced two significant changes that substantially increased employment costs for businesses:
| Earnings Band (Annual) | Employer NI Rate 2025/26 | Previous Rate (2024/25) |
|---|---|---|
| Up to £5,000 (Secondary Threshold) | 0% | 0% (was 0% up to £9,100) |
| Above £5,000 | 15% | 13.8% above £9,100 |
For a full-time employee on £35,000, the employer NI cost in 2025/26 is: 15% × (£35,000 − £5,000) = 15% × £30,000 = £4,500/year. Under the old 2024/25 rules: 13.8% × (£35,000 − £9,100) = 13.8% × £25,900 = £3,574.20/year. The increase is therefore £925.80 per year per employee in this example.
The Employment Allowance remains available to eligible smaller employers, currently set at £10,500 per year from April 2025 (increased from £5,000). This means qualifying businesses can reduce their employer NI bill by up to £10,500. Businesses with an employer NI bill of £100,000 or more in the previous year are ineligible.
Class 4: Self-Employed National Insurance
Self-employed individuals pay Class 4 NI on their profits through Self Assessment. Class 2 NI (a flat-rate weekly contribution) was abolished from April 2024 onwards. From April 2025, Class 4 rates are:
| Profit Band (Annual) | Class 4 Rate 2025/26 | Rate 2024/25 |
|---|---|---|
| Up to £12,570 (Lower Profits Limit) | 0% | 0% |
| £12,571 to £50,270 (Upper Profits Limit) | 6% | 9% |
| Above £50,270 | 2% | 2% |
A self-employed person with profits of £45,000 in 2025/26 would pay:
- 0% on first £12,570 = £0
- 6% on £32,430 (£45,000 − £12,570) = £1,945.80
- Total Class 4 NI: £1,945.80/year (£162.15/month)
NI Category Letters Explained
Every employee is assigned an NI category letter, which determines the rate of employee and employer contributions. The letter appears on payslips and PAYE records. The most common categories are:
| Letter | Who It Applies To | Employee Rate | Notes |
|---|---|---|---|
| A | Most employees (standard) | 8% / 2% | Default for employees not in other categories |
| B | Married women & widows with valid Reduced Rate Election | 3.85% / 2% | Historical — certificate must pre-date April 1977; very few people have this |
| C | Employees over State Pension age (currently 66) | 0% | Employer still pays 15% above Secondary Threshold |
| H | Apprentices under 25 | 8% / 2% | Employer pays 0% up to Upper Secondary Threshold (£50,270) |
| J | Employees deferring NI (another job) | 2% | Must apply to HMRC for deferment if primary job exceeds UEL |
| M | Employees under 21 | 8% / 2% | Employer pays 0% up to Upper Secondary Threshold (£50,270) |
| Z | Under 21 with NI deferment | 2% | Rarely used combination |
Categories H and M are beneficial for employers of young workers and apprentices, as they eliminate employer NI on earnings up to £50,270 per year. This is designed to incentivise the hiring of young people and apprentices.
National Insurance and Your State Pension
National Insurance contributions are the mechanism through which you build entitlement to the UK State Pension and other contributory benefits. The new State Pension (introduced April 2016 for those reaching State Pension age on or after 6 April 2016) requires:
- 35 qualifying years for the full new State Pension (£221.20/week in 2025/26)
- 10 qualifying years minimum to receive any State Pension
- Fewer than 35 qualifying years results in a proportionate reduction
A “qualifying year” is a tax year in which you have paid (or been credited with) sufficient NI contributions. For employees, you need earnings above the Lower Earnings Limit (£6,396/year in 2025/26) for a year to count. For the self-employed, profits above £6,725 trigger automatic NI credits since April 2024.
NI credits are also awarded in lieu of contributions for periods when you:
- Claim certain benefits (Universal Credit, Carer’s Allowance, ESA, etc.)
- Are a registered foster carer or kinship carer
- Take time off to care for a child and claim Child Benefit (Specified Adult Childcare credits)
- Are on jury duty
- Are between 16 and school-leaving age
Voluntary Class 3 Contributions
If you have gaps in your NI record, you may be able to pay voluntary Class 3 contributions to fill them. The rate for 2025/26 is £17.45 per week (£907.40 per year). Each year you fill counts as a qualifying year towards your State Pension.
The decision to pay voluntary contributions is essentially a financial calculation: the cost of filling a gap is weighed against the increase in State Pension you would receive. At the full new State Pension rate of £221.20/week (£11,502/year), each additional qualifying year (out of 35) adds approximately £6.32/week (£328.64/year). The payback period on a voluntary year costing £907.40 would therefore be approximately 2.8 years — making it excellent value for most people in good health.
Important rules around voluntary Class 3 contributions:
- Generally, you can fill gaps in your NI record going back up to 6 years
- However, until April 2025, a special scheme allowed gaps back to April 2006 to be filled at relatively low cost — this window has now closed
- If you are under State Pension age and already on track for the full State Pension, there is no benefit to making voluntary contributions
- Some gaps cannot be filled (e.g. if you were abroad or self-employed with low profits before certain dates)
Checking Your NI Record
HMRC maintains a record of every NI contribution and credit for your entire working life. You can access this via your Personal Tax Account at gov.uk. The record shows:
- Each tax year from age 16 and whether it is a “Full year”, “Year is not full” or “You did not make any contributions”
- Whether you can pay voluntary Class 3 contributions to top up each incomplete year
- Your forecast State Pension amount based on your current record
- The date you can start claiming your State Pension
It is wise to check your record every few years, as errors can occur — particularly if you have had multiple employers, periods of self-employment, or time abroad. Corrections must be made through HMRC, and it is easier to resolve discrepancies sooner rather than later.
National Insurance Numbers (NiNO)
Every person who is eligible to work in the UK is assigned a National Insurance Number (NiNO) in the format AB 12 34 56 C. The NiNO is used to:
- Record your NI contributions and tax payments with HMRC
- Match contributions to your State Pension record
- Identify you when claiming state benefits
- Verify your right to work for employers
UK citizens born in the UK are automatically issued their NiNO before their 16th birthday. Overseas nationals coming to work or study in the UK can apply for a NiNO online at gov.uk. You do not need a NiNO to start work, but you need one for your employer to correctly record your NI contributions. Keep your NiNO safe — it is used in identity fraud and should never be shared unnecessarily.
A Brief History of National Insurance
National Insurance was introduced by David Lloyd George’s Liberal government through the National Insurance Act 1911 — a landmark piece of social legislation that created the foundation of the modern welfare state. The original scheme was compulsory for workers in certain industries and provided limited health insurance and unemployment benefits in exchange for weekly contributions from workers, employers and the state.
The system was dramatically expanded after World War II as part of the Beveridge reforms. The National Insurance Act 1946, enacted by the Attlee government, created a comprehensive cradle-to-grave social security system funded by NI contributions, covering retirement pensions, sickness benefit, unemployment benefit, death grants and other benefits for the first time.
Key milestones since then include:
- 1975: Introduction of earnings-related NI contributions, replacing the flat-rate system
- 1999: Introduction of the Working Families Tax Credit and Working Tax Credit, interacting with NI thresholds
- 2016: New State Pension introduced, requiring 35 qualifying years
- 2022: Brief 1.25% Health and Social Care Levy introduced alongside NI, then reversed in November 2022
- January 2024: Employee NI cut from 12% to 10%
- April 2024: Employee NI cut further to 8%; Class 2 NI abolished
- April 2025: Employer NI increased from 13.8% to 15%; Secondary Threshold reduced to £5,000
Frequently Asked Questions
On a salary of £35,000, your employee Class 1 NI for 2025/26 is calculated as: 0% on the first £12,570 (Primary Threshold), then 8% on £22,430 (£35,000 minus £12,570) = £1,794.40 per year, or approximately £149.53 per month. No NI is payable below £12,570.
From April 2025, the most significant change was for employers: the employer (secondary) NI rate increased from 13.8% to 15%, and the Secondary Threshold was reduced from £9,100 to £5,000 per year. For employees, rates stayed at 8% (£12,570–£50,270) and 2% above £50,270. For the self-employed, Class 4 NI was cut from 9% to 6% on profits between £12,570 and £50,270.
You need 35 qualifying years of National Insurance contributions or credits to receive the full new State Pension (£221.20 per week in 2025/26). You need at least 10 qualifying years to receive any State Pension at all. If you have gaps, you may be able to fill them by paying voluntary Class 3 contributions at £17.45 per week (2025/26). Check your NI record at gov.uk via your Personal Tax Account.
No. Once you reach State Pension age (currently 66 for both men and women), you stop paying employee National Insurance contributions even if you continue to work. You are placed on NI Category C. However, your employer continues to pay employer’s NI at 15% on your earnings above £5,000 per year.
Class 1 is paid by employees and employers on earnings. Class 2 (self-employed flat rate) was abolished April 2024. Class 3 is voluntary contributions to fill gaps in your NI record (£17.45/week in 2025/26). Class 4 is paid by the self-employed on profits above £12,570: 6% on profits from £12,570 to £50,270, then 2% above £50,270.
Yes. You can view your NI record through your HMRC Personal Tax Account at gov.uk/check-national-insurance-record. You will need a Government Gateway account. The record shows all qualifying years, gaps, and your State Pension forecast. You can also see which gaps you can fill with voluntary contributions.
A National Insurance number (NiNO) is a unique personal reference in the format AB 12 34 56 C. UK citizens receive it automatically before age 16. Overseas nationals coming to work or study in the UK can apply online at gov.uk. You must have the right to work or study in the UK. You can start work before receiving your NiNO, but you need one for your contributions to be correctly recorded.