UK · 2026 to 2027 tax year
Pro rata salary calculator
| Item | Year | Month |
|---|---|---|
| Pro rata salary (60% of full time) | £18,000.00 | £1,500.00 |
| Income tax (PAYE) | −£1,084.00 | −£90.33 |
| National Insurance | −£433.92 | −£36.16 |
| Take-home pay | £16,482.08 | £1,373.51 |
Worked example: £30,000 at 22.5 hours
- Work out the fraction of full time: 22.5 ÷ 37.5 = 0.6, or 60%.
- Multiply the full-time salary by it: £30,000 × 0.6 = £18,000 a year.
- Divide for each payday: £18,000 ÷ 12 = £1,500 a month, or £18,000 ÷ 52 = £346.15 a week.
- The hourly rate stays the same as full time: £30,000 ÷ (37.5 × 52) = £15.38 an hour.
- Tax for 2026/27 on tax code 1257L: income tax £1,084 and employee National Insurance £433.92 a year, so take-home pay is £16,482.08, about £1,373.51 a month.
Tax worked out with HMRC's 2026/27 PAYE and National Insurance rules, the same routines as the take-home pay calculator. No pension or student loan. General information, not tax advice.
Pro rata salary for common part-time hours
| Hours a week | Fraction | Pro rata salary | Per month |
|---|---|---|---|
| 30 | 80% | £24,000 | £2,000 |
| 25 | 66.67% | £20,000 | £1,666.67 |
| 22.5 | 60% | £18,000 | £1,500 |
| 18.75 | 50% | £15,000 | £1,250 |
| 15 | 40% | £12,000 | £1,000 |
Holiday is pro rata too. A part-time worker on regular days gets 5.6 times the days they work a week: 3 days a week gives 16.8 days a year. GOV.UK's part-time workers' guidance says part-time staff must get the same pay rates as comparable full-time staff, with benefits in proportion to their hours.
The official method, step by step
- Divide the part-time hours a week by the full-time hours a week for the same job. That fraction is the share of full time.
- Multiply the full-time salary by the fraction. For a term-time contract that pays for fewer than 52 weeks, multiply again by the paid weeks ÷ 52.
- Split the pro rata salary into paydays: ÷ 12 for monthly, ÷ 52 for weekly.
- Run the result through PAYE and National Insurance for 2026/27: tax-free pay from the tax code, 20% on the next £37,700, then 40% and 45%; employee National Insurance 8% on monthly earnings from £1,048 to £4,189 and 2% above.
What this leaves out
- Pension contributions and student loan repayments (use the take-home pay calculator for pension)
- Term-time formulas that add holiday weeks to the paid weeks: enter the paid weeks your contract sets
- Overtime, which part-time workers may not get until they work more than full-time hours
- Pro rata for starting or leaving part way through the year: use the holiday pay calculator for the holiday share
Sources: GOV.UK, Part-time workers' rights (same pay rates as comparable full-time workers; benefits applied pro rata to hours worked; full time usually 35 hours or more a week); GOV.UK, Holiday entitlement (part-time regular hours: 5.6 × days worked a week); HMRC, Specification for PAYE Tax Table Routines, version 24.0 (February 2026), Appendices A–C; HMRC, Rates and thresholds for employers 2026 to 2027; HMRC, 2026 to 2027: Employer further guide to PAYE and National Insurance contributions (CWG2).
Pro rata salary calculator: common questions
How do you calculate a pro rata salary?
Multiply the full-time salary by the part-time hours, then divide by the full-time hours. £30,000 for a 37.5-hour week becomes £18,000 for 22.5 hours, because 22.5 is 60% of 37.5.
What does pro rata mean on a job advert?
That the salary shown is the full-time figure, and you'll be paid the share that matches your hours. “£30,000 pro rata” for 3 days of a 5-day week means £18,000 a year.
Is the hourly rate lower for part-time work?
No. A pro rata salary keeps the same hourly rate as full time. GOV.UK says part-time workers should get the same pay rates as equivalent full-time workers.
How many hours is full time in the UK?
There is no legal number. GOV.UK says a full-time worker will usually work 35 hours or more a week; use the full-time hours for the same job at your employer.
How much is £18,000 pro rata after tax?
For 2026/27 on tax code 1257L, with no pension or student loan, about £16,482.08 a year after £1,084 income tax and £433.92 National Insurance, or about £1,373.51 a month.
Is holiday pro rata as well?
Yes. Statutory holiday is 5.6 weeks of the days or hours someone works, so a part-time worker on 3 days a week gets 16.8 days a year, capped at 28 days for anyone.
Can I make a payslip from this?
Yes. “Make the payslip with these numbers” opens the payslip generator with a month of the pro rata salary, its income tax and National Insurance filled in. Every line can be edited.
Need a payslip for this pay?
Free to create and preview. No account or card.