How pro-rata pay works
Pro-rata is Latin for "in proportion", and that is the whole trick: you are paid the full-time salary scaled to the share of a full-time week you actually work.
The hourly rate stays identical to a full-time colleague's; only the number of hours changes. Job adverts usually quote the full-time equivalent (FTE) salary, so this is the sum that turns an advertised "£30,000 FTE" into your actual pay.
Worked examples
Things worth checking on a part-time offer
- The full-time baseline. A £30,000 FTE against 40 hours is a lower hourly rate than the same figure against 37.5. Always ask what full-time means.
- Holiday. Statutory leave scales with your week too: 5.6 weeks of your pattern, not the full-timer's 28 days.
- Take-home. Tax bands do not scale: the personal allowance is the same whatever your hours, so part-time pay is taxed relatively lightly. Run your pro-rata figure through our take-home pay calculator to see the real monthly number.
Frequently asked questions
How is pro-rata salary worked out?
Divide your weekly hours by the full-time weekly hours, then multiply the full-time salary by that fraction. On 22.5 hours against a 37.5-hour week you work 60%, so a £30,000 full-time salary becomes £18,000.
What counts as full-time hours?
There is no legal definition, but 37.5 hours is the most common UK full-time week, with 35 to 40 hours all normal. Use whatever the job advert or contract states as full-time, since that is the basis your employer will use.
How do I calculate pro-rata from days instead of hours?
Divide days by 5 and use that fraction, assuming a 5-day full-time week. Three days a week is 3 ÷ 5 = 60% of the full-time salary, exactly equivalent to entering 22.5 hours against 37.5.
Does part-time work change my hourly rate?
No. Pro-rata means proportional: you earn the same hourly rate as a full-time colleague, just for fewer hours. If the numbers you are offered work out to a lower hourly rate, that is not pro-rata and is worth querying.
Is holiday also pro-rata?
Yes. Statutory holiday scales with your working pattern: 5.6 weeks of whatever your week looks like. Our holiday entitlement calculator does that sum.