Example result based on the prefilled values.
Annual NI
£1,793.28
Monthly NI
£149.44
Effective Rate
5.12%
Continue your plan
Useful next calculations
Rates & sources2026/27
2026/27 Category A Class 1 employee NI using weekly thresholds; actual payroll deductions depend on pay frequency and category letter.
Source: HMRC — National Insurance rates and categories — source checked for 2026/27.
When to use this calculator
- Before accepting a pay change, bonus, pension contribution, or salary-sacrifice option.
- When you want to compare employed, self-employed, or dividend-based income scenarios.
- When you need a simple take-home estimate before running payroll or filing returns.
- When you are approaching the £100,000 income level and want to understand the personal allowance taper effect.
- When you are planning a salary sacrifice arrangement and need to see the net pay impact before agreeing terms.
Worked example: £45,000 salary
Use these sample inputs as a quick scenario test, then change one variable at a time to compare outcomes.
Gross salary
£45,000
Below threshold (£12,570)
£0 NI
£12,570 → £45,000 × 8%
£2,594
Above £50,270
£0
Total employee NI
£2,594
Effective NI rate
5.77%
Salary-sacrificing 5% (£2,250) into pension cuts NI to £2,414.40 — a £180/year saving on top of income-tax relief.
How to read your results
Annual NI
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
Monthly NI
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
Effective Rate
The effective rate lets you compare options on a true like-for-like basis rather than being misled by different compounding periods or fee structures. Use it to cut through headline marketing rates when shortlisting providers or products.
Method & assumptionsAuthoritative sources
This calculator estimates 2026/27 Category A employee Class 1 National Insurance by converting annual salary to weekly earnings, then applying the HMRC weekly Primary Threshold of £242, Upper Earnings Limit of £967, main rate of 8% and upper rate of 2%.
It does not calculate employer National Insurance, self-employed Class 4 contributions, voluntary Class 3 contributions or the special annual method for company directors. Actual payroll deductions are calculated per pay period and can differ because of pay frequency, irregular earnings, category letters and rounding. Check your payslip or HMRC guidance for an exact liability.
Common mistakes
- !Entering gross income when you really want take-home pay, or vice versa.
- !Ignoring pension contributions, deductions, or local tax rules that change the result.
- !Comparing monthly and annual figures without standardising them first.
- !Overlooking the National Insurance threshold changes that apply mid-year when rates or bands are adjusted in a Budget.
- !Assuming a salary sacrifice benefit reduces take-home pay by the full gross amount, rather than only the after-tax cost.
What to do next
- Check the same scenario with related pay or deduction calculators to see the full picture.
- Keep a copy of the assumptions you used so you can compare next tax year or pay period accurately.
- Read the related guides below if you are choosing between multiple income or deduction options.
- If you are self-employed, run the self-employment tax calculator alongside this result to compare the net position against employed income.
- Check whether increasing your pension contribution by even one or two percent changes the take-home significantly — use the pension calculator next.
Go deeper — 4 guides reference this calculator
- 9m
UK Tax Year 2025/26: Complete Guide to Allowances, Bands & Thresholds
Full reference for the 2025/26 UK tax year — income tax bands, Personal Allowance, National Insurance, ISA allowance, pension limits, stamp duty changes.
- 10m
UK Self-Employed Tax Guide: Self Assessment, Payments on Account, Allowable Expenses
How self-employed tax works in the UK — registering with HMRC, the Self Assessment deadline, payments on account, what you can claim, and Class 2/4 NI.
- 7m
Pay Rise Calculator Guide: What a Gross Raise Becomes After Tax, NI and Pension
Turn a gross salary increase into a real take-home figure by checking tax, National Insurance, pension contributions and inflation together.
- 6m
UK Tax Code Guide: 1257L, K Codes, Emergency Codes and What to Do
How to read a UK tax code, what common letters mean, why emergency codes happen, and how to check your payslip against the right net pay.
Frequently asked
Use arrow keys to navigate items, Enter or Space to expand/collapse.