Estimate how a bonus may affect UK income tax, National Insurance, student loan repayments, and take-home pay.
Use this bonus tax calculator to compare an annual salary before and after a one-off bonus. The estimate shows the bonus kept after PAYE, National Insurance and supported student-loan deductions, with a payroll timing caveat because real payslips can vary.
A bonus is taxed as ordinary pay. Enter your salary and the bonus.
Of £40,000.00 gross a year: Income Tax £5,486.00, National Insurance £2,194.40, Take-home £32,319.60.
Those twelve months add up to the year exactly. A real payslip may not: if your code is W1, M1 or X, the bonus month is taxed as though that month's pay repeated all year and the excess comes back later, and National Insurance is worked out per pay period rather than across the year.
Of the £5,000, you keep £3,600. The rest goes to Income Tax and National Insurance at your marginal rate.
Saving £135 a month — about 5% of this take-home — becomes £8,934.17 in five years at an example 4%: try the savings calculator.
2026/27 rates, England, Wales and Northern Ireland, no student loan. Open the full calculator to change region, student loan or pension method.
Payslip showing different figures? The payslip checker works out what your pay and tax code should have produced and shows which assumption could explain the gap.
Planning estimate only. Pay-event outputs cannot confirm real payroll treatment, HMRC records, employer policy, employment terms, or payslip timing.
| Tax year | 2026/27 |
|---|---|
| Income Tax impact | £1,000 |
| National Insurance impact | £400 |
| Student loan impact | £0 |
A cash bonus is modelled as taxable employment earnings added to annual pay. Real payslips can look different when payroll annualises or recovers tax through a pay period.
| Tax/source year | 2026/27 |
|---|---|
| Region | England/Wales/Northern Ireland |
| Tax code basis | 1257L where the page uses PAYE defaults |
| Pension basis | No pension deduction unless this example says otherwise |
| Student loan basis | No student loan unless selected in this example |
| Gross pay | Employment pay before PAYE deductions and pension or loan settings. |
|---|---|
| Income Tax | Tax estimated from the selected tax-year, region, tax code and taxable-pay assumptions. |
| National Insurance | Employee NI is calculated separately from Income Tax and may not follow the same bands. |
| Pension and loans | Pension method and student-loan plan can change take-home pay and payslip comparisons. |
| Pension contribution | Changing the rate or method can change taxable income, National Insurance and take-home pay. |
|---|---|
| Tax code and region | Scottish Income Tax, Welsh codes, emergency tax or a non-standard tax code can move the result. |
| Student loan plan | A different plan can change deductions because each plan uses its own threshold and repayment rate. |
| Bonus, overtime or second job | Extra pay and payroll timing can make a real payslip differ from the smooth annual estimate. |
| Tax code | HMRC tax-code changes, K codes, BR/D codes, or emergency markers can change PAYE deductions. |
|---|---|
| Cumulative basis | Week 1, Month 1 or non-cumulative payroll can differ from a smooth annual calculator estimate. |
| Pension method | Relief at source, net pay and salary sacrifice can affect taxable pay and take-home pay differently. |
| Payroll timing | Bonus, overtime, arrears, refunds, cut-off dates and corrections can all move a single payslip. |
| Why is the tax on my payslip higher than expected? | payslip difference |
|---|---|
| What do the main payslip lines mean? | payslip explainer |
| What tax code should I use for modelling? | tax code |
| How much does pension reduce take-home pay? | pension comparison |
| How does this affect a monthly budget? | budget planning |
| What is not decided here | PayBreakdown does not decide payroll correctness, lender approval, benefit entitlement or employer compliance, and does not give regulated financial, mortgage, debt, tax, payroll or legal advice. |
|---|
The figures on this page are worked from bonus tax, using the values below. Open the calculator if your example salary differs.
The estimate treats the bonus as taxable employment income added to annual pay. Payroll systems can tax a bonus heavily in the pay period and then correct the annual position later.
This estimate is worked out on £35,000 annual gross. Change any of those and the take-home figure moves; pension method and student loan plan usually move it most. A payslip can differ from any calculator because payroll works pay period by pay period, so a tax-code change, a bonus, arrears or a refund can land in one month and not the next. See how each deduction is worked out.
Enter annual salary and bonus amount to estimate the bonus kept after Income Tax, National Insurance and supported student-loan deductions.
A cash bonus is usually treated as taxable employment income. It can feel different because it is added to one pay period and may be taxed at your marginal rate.
Payroll timing, tax-code operation and annualised deductions can make a one-off bonus payslip look different from the final annual tax position.
Last updated 2026-08-27. Checked by Sean Elsmore. Rates last checked against GOV.UK on 2026-08-07. Estimates are for planning and should be checked against official records where the decision matters.