Type the salary you are about to offer and see what it actually costs you a year, a month and an hour on the rates in force from 6 April 2026: 15% employer NI above a £5,000 threshold, the £10,500 Employment Allowance as a pot that runs out, and pension on the qualifying earnings band.
| Total cost to employ | — | £ / year |
|---|---|---|
| Cost per month | — | £ |
| On-cost on top of the salary | — | % |
| True cost per hour worked | — | £ |
| Employer NI before Employment Allowance | — | £ / year |
| Employment Allowance this hire uses up | — | £ |
| Employer NI you actually pay | — | £ / year |
| Employer pension | — | £ / year |
| Apprenticeship Levy | — | £ / year |
| Checks | — |
Free for the file open in your editor - no key, no limit. The workspace sweep and the report ask for a key.
Firefox Add-onsDownload the worked hire as a .csv row - every input and every figure - so the number you approved is on file with the budget, the offer and the board paper instead of living in a browser popup.
One payment, one licence key for this tool. The key is shown right after payment.
A managed UK payroll bureau runs £4-12 per employee a month with a £30-150 setup fee, and it only starts once you have already hired.
Buy the full version — $60I have a key· ReadyStack
Real numbers from this tool, line by line.
Ask any chatbot what an employer pays in National Insurance and you will very likely get 13.8% on everything above £9,100 a year. That answer was correct until 5 April 2025. It has been wrong for two tax years, and it is still the number sitting in a great many spreadsheets.
From 6 April 2026, for the 2026/27 tax year, the figures are these: employer Class 1 National Insurance is 15%, and it starts at a secondary threshold of £5,000 a year, not £9,100. The threshold moved down and the rate moved up, which pushes the same hire in the same direction twice.
Take a £32,000 salary. On the old figures you would budget (£32,000 − £9,100) × 13.8% = £3,160. On the 2026/27 figures it is (£32,000 − £5,000) × 15% = £4,050. That is £890 a year you did not put in the budget, per head, before you have added a single other cost.
The Employment Allowance is a pot, not a discount. It is £10,500 for 2026/27, and the £100,000 eligibility cap has gone, so far more employers can claim it. But it is £10,500 per *business*, per *year* — not per employee. Our £32,000 hire takes £4,050 out of it and leaves £6,450 for everyone else. Budget the full allowance against each hire in turn and your second and third hires will both look free.
Pension is charged on a band, not on the salary. The 3% employer minimum applies to qualifying earnings between £6,240 and £50,270. On a £30,000 salary that is 3% of £23,760 = £713, not 3% of £30,000 = £900. The £187 gap runs the other way for part-timers, and it is capped at the top: an £80,000 hire still only pensions the band, £1,321 at the minimum.
Under-21s, apprentices under 25 and veterans in their first civilian year pay 0% up to £50,270. Not up to £5,000 — up to £50,270. A 20-year-old on £24,000 costs the employer £0 in National Insurance rather than £2,850. That is the single largest swing in the whole calculation, and it is the one most often missed, because it is a property of the person rather than of the job.
The National Living Wage is £12.71 an hour from April 2026 for workers aged 21 and over. On a 37.5-hour week that is £24,784.50 a year. A £24,000 full-time salary — a number that still looks perfectly ordinary written down — is below the legal minimum from April 2026. It is worth catching that at the offer stage rather than at the first payroll run.
Put it together for a £32,000 hire at 37.5 hours, with the allowance already used on existing staff and £1,500 of laptop, software and insurance:
| Salary | £32,000 |
| Employer NI (15% above £5,000) | £4,050 |
| Employer pension (3% of the band) | £773 |
| Equipment, software, insurance | £1,500 |
| Total cost to employ | £38,323 |
| Cost per month | £3,194 |
| On-cost on top of the salary | 19.8% |
| True cost per hour worked | £19.65 |
Roughly a fifth on top, and the per-hour figure is the one that makes a hire comparable with a day rate.
The two obvious free routes both miss. A chatbot answers from what it learned, and what it learned about employer NI is mostly pre-April-2025. HMRC's own calculators are built to run a payroll for somebody who already works for you; they are not built to price a hire you have not made yet, which is the exact moment the money is decided.
That gap is what this extension fills. It sits in the browser, you type the salary and the category, and it answers on the 2026/27 rates with the allowance treated as a pot and the pension charged on the band. The calculation is free, uncapped, and also runs as a single web page. The $60 licence adds exporting the worked hire as a .csv, so the figure you approved ends up on file next to the budget rather than in a browser popup you closed.
*Figures: gov.uk, "Rates and thresholds for employers 2026 to 2027"; auto-enrolment qualifying earnings band and £10,000 trigger; National Living Wage from April 2026.*
It prices a UK hire before you make the offer. You type the salary, the employee's category and the Employment Allowance you have left; it returns employer National Insurance at 15% above the £5,000 secondary threshold, employer pension on qualifying earnings, the Apprenticeship Levy, the total yearly and monthly cost, and the true cost per hour worked.
UK employers deciding whether they can afford a hire: small business owners, office and practice managers, recruiters quoting a client the full cost of a placement, and finance leads building a headcount budget. It is written for the person who signs off the offer, not for a payroll clerk running a live payroll.
Both give you the wrong number. General AI answers still quote 13.8% employer NI above a £9,100 threshold, the figures that stopped applying in April 2025; on a £32,000 salary that understates the cost by £890 a year. HMRC's tools run payroll for someone already employed, so they cannot price a hire you have not made yet.
The calculation is free and uncapped: every category, every salary, in the extension popup or on the web page, with no key, no watermark and no trial limit. The $60 licence adds one thing on a different axis, a .csv export of the worked hire with every input and every figure, so the number you approved leaves the browser and goes on file.
A managed UK payroll bureau charges roughly £4 to £12 per employee a month with a £30 to £150 setup fee, and it only starts once the person is already hired. This is a one-off $60 and it answers the question at the point that decides the money, which is before the offer goes out.
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