Pro-rata salary calculator
Work out a part-time salary from the full-time one: their pay a year, a month and a week for their hours, at the same hourly rate as full time.
The rule used
Part-time staff are paid at the same rate as full time, for their hours.
Their salary is the full-time salary times their hours over the full-time hours. Holiday is pro rata too: see our holiday entitlement calculator, and check the hourly rate in our minimum wage checker.
Source: Part-time workers’ rights, GOV.UK (opens in a new tab), checked 2 Nov 2026
This calculator gives the legal minimum as guidance, not legal advice. For one person’s situation, check their contract, or ask Acas (0300 123 1100, free) or a solicitor.
Pro-rata salary questions.
How do you work out a pro-rata salary?
Divide their hours a week by the full-time hours, and multiply the full-time salary by that. Someone working 22.5 of 37.5 hours gets 60% of the full-time salary.
Must part-time staff get the same rate?
Yes. Part-time workers must be treated no less favourably than comparable full-time workers: the same hourly rate, and bonuses and other pay pro rata to their hours.
Do part-time workers get overtime?
Not always: overtime rates can start only once they work more than the full-time hours.
What about holiday?
They get 5.6 weeks of their own working week. Someone working 3 days a week gets 16.8 days. Our holiday calculator works it out, for starters and leavers too.
What about term-time staff?
Term-time pay depends on the contract, including how their paid holiday is spread through the year. This calculator works out part-time hours only.
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