Bonus take-home pay calculator
A bonus is taxed at your marginal rate, not some special bonus rate. The reason your bonus month payslip still looks wrong is that cumulative PAYE briefly assumes you are going to earn that much every month.
That is £35,920 a year after income tax, National Insurance and anything else coming off your pay.
- Income tax
- £6,486
- National Insurance
- £2,594
- Effective rate
- 20.2%
- Marginal rate
- 28.0%
| Year | Month | Week | Hour | |
|---|---|---|---|---|
| Gross pay | £45,000.00 | £3,750.00 | £865.38 | £23.08 |
| Income tax | £-6,486.00 | £-540.50 | £-124.73 | £-3.33 |
| National Insurance | £-2,593.92 | £-216.16 | £-49.88 | £-1.33 |
| Take-home pay | £35,920.08 | £2,993.34 | £690.77 | £18.42 |
What a bonus is worth at your salary
| Salary | Bonus | Net gain | You keep | Marginal rate |
|---|---|---|---|---|
| £28,000 | £5,000 | £3,600 | 72.0% | 28.0% |
| £38,000 | £5,000 | £3,600 | 72.0% | 28.0% |
| £48,000 | £5,000 | £3,218 | 64.4% | 28.0% |
| £55,000 | £5,000 | £2,900 | 58.0% | 42.0% |
| £75,000 | £5,000 | £2,900 | 58.0% | 42.0% |
| £102,000 | £5,000 | £1,900 | 38.0% | 62.0% |
| £120,000 | £5,000 | £1,900 | 38.0% | 62.0% |
On £45,000, a £5,000 bonus adds £3,600 to your year — about £300.00 a month if you spread it. The gap between the headline and the landing figure is £1,400, and none of it is a mistake.
Why the bonus month payslip looks worse than this
PAYE is cumulative. In the month a bonus lands, the system looks at your pay so far, annualises it, and taxes you as though every remaining month will look the same. If a £5,000 bonus arrives in month three, PAYE briefly behaves as though you are on a much larger salary and takes tax accordingly.
It corrects itself. Over the following months your cumulative position falls back into line and the over-deduction comes back through smaller tax bills, without you doing anything. By March the total is right. If you leave the job before then, you will have overpaid and should claim it back — the mid-year leaver guide explains how.
Putting the bonus into the pension instead
Bonus sacrifice is the cleanest use of salary sacrifice there is, because you never see the money and never adjust to it. A £5,000 bonus sacrificed entirely costs you £3,600 of take-home and puts the full £5,000 into the pension, plus whatever your employer adds from their own National Insurance saving. At a 42% marginal rate that is a meaningful trade; inside the Personal Allowance taper it is close to unarguable.
Questions people actually ask
Are bonuses taxed at 40%?
A bonus is taxed at whatever your marginal rate is once the bonus is added to your salary. There is no separate bonus rate in the UK. What people are usually noticing is that the bonus pushed part of their income into the higher rate band for the first time.
Why did I lose more than half my bonus?
Either you crossed into the £100,000 to £125,140 taper, where the effective rate on that slice is 62% before a student loan, or cumulative PAYE over-deducted in the bonus month and has not corrected yet. Both are common; only one is permanent.
Will I get the extra tax back?
If it was a cumulative PAYE over-deduction, yes, automatically, over the remaining months of the tax year. If the bonus genuinely took you into a higher band, no.
Does a bonus affect my student loan?
Yes. Student loan is deducted on your National Insurance-able earnings in the period, so a bonus month produces a much larger loan deduction. Unlike tax, that one does not come back — student loan is worked out per period and never reconciled across the year.
Related
- Pay rise calculatorA permanent rise, priced the same way.
- Sacrifice the bonusWhat it buys and what it costs.
- Why the payslip looks wrongCumulative PAYE, explained.
Figures on this page are for the 2026/27 tax year (6 April 2026 to 5 April 2027) and were last checked on 29 August 2026. Every rate we use is listed on the sources page.