Pro-rata salary calculator
A pro-rata salary is the full-time figure scaled to the days or hours worked; for 2026/27 the calculation is unaffected by pro-rating because the £12,570 personal allowance stays the same for everyone, under HMRC's Income Tax rates. This calculator estimates the pro-rata gross and the take-home pay after tax and National Insurance.
What is £35,000 pro-rata for 3 days a week?
| Basis | Gross | Take-home |
|---|---|---|
| Full-time equivalent | £35,000 | £28,720 |
| Your pro-rata (60.0%) | £21,000 | £18,640 |
How is pro-rata pay calculated?
Pro-rata pay is the full-time salary multiplied by the share of the week worked. Dividing the hours or days worked by the full-time hours or days gives the fraction, which is then applied to the salary. Three days against a five-day week is a fraction of 0.6, so a £30,000 full-time role pays £18,000 pro-rata. Days and hours both work, as long as both figures use the same unit.
Tax follows the actual pay, not the advertised salary. The personal allowance stays at £12,570 whatever the hours worked, under HMRC's Income Tax rates, so a smaller salary shelters a larger share under it. That is why the take-home percentage on a part-time wage is often higher than on the full-time figure, and why very low pro-rata pay can fall out of income tax altogether.
What would I earn on a worked example?
Take a £35,000 full-time salary and 3 days against a 5-day week. That is 60.0% of full time, so the pro-rata gross is £21,000. After £1,686 income tax and £674 National Insurance, the estimated take-home is about £18,640 a year, near £1,553 a month.
Common questions
What does pro-rata salary mean?
Pro-rata means in proportion. A job advertised at a full-time salary but worked part-time pays a share of that figure, based on how many hours or days you do against the full-time week. Three days against a five-day week is three-fifths of the full salary.
What is £35,000 pro-rata for 3 days a week?
Working 3 days against a 5-day week is 60.0% of full time. On a £35,000 full-time salary that is about £21,000 gross a year, with a take-home of roughly £18,640 after tax.
How do I pro-rata by hours instead of days?
Enter your part-time hours as the part figure and the full-time hours as the full figure, for example 22.5 against 37.5. The tool divides one by the other, so days or hours both work as long as you use the same unit for both boxes.
Is a pro-rata salary taxed less?
You pay tax on the actual pro-rata pay, not the full-time figure. Because the personal allowance is fixed, a lower salary keeps more of each pound. A part-time salary under £12,570 pays no income tax at all, so the effective deduction is smaller than on the full-time equivalent.
Does pro-rata affect my holiday too?
Usually yes. Holiday entitlement is normally pro-rated the same way as pay, so part-time staff get a proportional share of the full-time holiday allowance. This tool covers pay only, not leave.
How is pro-rata pay calculated?
Pro-rata pay is the full-time salary multiplied by the share of the working week actually worked. Divide the hours or days worked by the full-time hours or days to get that fraction, then apply it to the salary. Three days against a five-day week is a fraction of 0.6, so a £30,000 full-time role pays £18,000 pro-rata. Tax then follows the actual pro-rata pay, not the advertised full-time figure, under HMRC's Income Tax rates.
What would I earn on a worked example?
Take a £35,000 full-time salary and 3 days against a 5-day week. That is 60.0% of full time, so the pro-rata gross is £21,000. After £1,686 income tax and £674 National Insurance, the estimated take-home is about £18,640 a year, near £1,553 a month.
Sources & Rate Verification
Rates verified against official statutory guidance on 6 September 2026.