The pro rata formula
Pro rata salary = full-time salary × your hours ÷ full-time hours
Example: £30,000 FTE, 22.5 of 37.5 hours → 30,000 × 0.6 = £18,000 a year, £1,500 a month.
Common part-time patterns
| Days a week | FTE | £25,000 FTE | £30,000 FTE | £40,000 FTE |
|---|---|---|---|---|
| 1 | 0.2 | £5,000 | £6,000 | £8,000 |
| 2 | 0.4 | £10,000 | £12,000 | £16,000 |
| 2.5 | 0.5 | £12,500 | £15,000 | £20,000 |
| 3 | 0.6 | £15,000 | £18,000 | £24,000 |
| 4 | 0.8 | £20,000 | £24,000 | £32,000 |
Related
Part-time holiday is pro rata too: check it with the holiday entitlement calculator. Working extra hours on a salary? The overtime calculator turns your salary into an hourly rate and adds time and a half. To convert any pay between hourly, weekly, monthly and yearly, use the hourly to salary calculator.
FAQ
What does pro rata salary mean?
Pro rata means "in proportion". A pro rata salary is the full-time salary scaled down to the hours you actually work. A job advertised at £30,000 pro rata for 22.5 hours a week, where full time is 37.5 hours, pays 22.5 ÷ 37.5 = 60% of £30,000, so £18,000 a year.
How do I calculate a pro rata salary?
Divide your weekly hours by the full-time weekly hours, then multiply by the full-time salary. Pro rata salary = FTE salary × (your hours ÷ full-time hours). For 3 days a week out of 5 that is 3 ÷ 5 = 0.6, the same as using hours if your days are the same length.
What is FTE?
FTE stands for full-time equivalent. 1.0 FTE is a full-time job; 0.6 FTE is 60% of full time, for example 3 days out of 5. Employers often advertise part-time jobs with the FTE salary and the FTE so you can work out the real pay.
How is salary worked out if I start or leave mid-year?
Most employers pay for the calendar days you were employed: annual salary × days employed ÷ days in the year. Open "Starting or leaving during the year?" and enter your dates. Some payroll systems use working days or months instead, so your payslip can differ by a few pounds.
Do part-time workers get the same hourly rate?
Yes. In the UK, the Part-time Workers Regulations 2000 say part-timers must not be treated less favourably than comparable full-time staff, so the hourly rate should be the same and benefits like holiday are pro rata.
Is the result before or after tax?
Before tax. The calculator shows gross pay. Income tax, National Insurance and pension contributions come off afterwards and depend on your tax code.
Legal basis and sources
- GOV.UK: Part-time workers’ rights
- legislation.gov.uk: Part-time Workers (Prevention of Less Favourable Treatment) Regulations 2000
- GOV.UK: Holiday entitlement
For information only. Your contract or specific circumstances may change the result.