Pro rata salary calculator
A job advertised at a full-time salary, scaled to the hours you would actually work, with the take-home pay that goes with it.
How this is calculated
The pro rata salary is the full-time figure multiplied by your hours divided by the full-time week. Nothing else about the job changes it.
That reduced salary then goes through the normal PAYE calculation, which is where part-time work often lands better than expected: the personal allowance is the same whatever your hours, so a smaller share of your pay is taxed.
Holiday entitlement is also pro rata, so a part-time worker gets 5.6 weeks of their own working pattern rather than a full-time week.
Some benefits do not scale. A flat car allowance or a health plan may be the same regardless of hours, which quietly makes part-time work better value. Those are not included here.
Rates used · 2026/27
| Personal allowance | £12,570, the same at any hours |
| Basic rate 20% | £12,571 to £50,270 |
| Employee NI 8% | above £12,570 |
| Statutory holiday | 5.6 weeks, pro rata |
Last checked July 2026. Source: HMRC and gov.uk.
Worked example
A £35,000 full-time job at 37.5 hours, worked at 22.5 hours a week, is 60% of full time and pays £21,000. Take-home is £1,483 a month. That is more than 60% of the full-time take-home, because the £12,570 personal allowance does not shrink with your hours.
Common questions
Why is my take-home more than the same share of the full-time take-home?
Because the personal allowance does not scale with hours. You still get the full £12,570 tax free, so proportionally less of a part-time salary is taxed.
Does the pension percentage stay the same?
Usually, since it is a percentage of what you earn. Auto-enrolment only applies above an earnings trigger, so very low hours may fall outside it.
What about holiday?
Statutory holiday is pro rata. At three days a week you get 5.6 times three days, not the full-time entitlement.
Is term-time only the same thing?
No. Term-time roles are usually pro rata on both hours and weeks, so use the hourly rate calculator with a lower weeks figure instead.