What does pro rata mean? Part-time salary explained

Job adverts often show a salary followed by “pro rata”. It means the figure is the full-time salary, and you’ll be paid a proportion of it if you work fewer hours. This guide explains how to work out what you’ll actually earn, how holiday works, and what you’ll take home after tax.

What pro rata means

Pro rata is Latin for “in proportion”. A salary advertised as £30,000 pro rata is the amount you’d earn working the full-time hours for that job. If you work part-time, your salary is reduced in proportion to your hours. The same applies to holiday, and often to other benefits such as employer pension contributions.

The full-time week varies between employers and roles. It’s often 37.5 hours, but it can be 35, 37, 40 or something else. Always check the full-time hours for the role you’re applying for, because it changes the result.

The pro-rata formula

To work out your pro-rata salary:

1. Divide your contracted hours by the full-time hours for the role.
2. Multiply the full-time salary by the result.

You can use days instead of hours if everyone works the same length of day. For example, working three days of a five-day week means three-fifths of the full-time salary.

The same calculation works for hourly pay. Dividing a full-time salary by 52 weeks and by the full-time hours gives the hourly equivalent, which you can multiply by your own hours.

Worked example

Say a job pays £30,000 pro rata, the full-time week is 37.5 hours, and you’ll work 22.5 hours a week.

• Your hours are three-fifths of full-time.
• Your pro-rata salary is £18,000 a year.
• After income tax and National Insurance, with no pension or student loan, you’d take home about £1,373.30 a month.
• Full-time at £30,000, you’d take home £2,093.30 a month.

Your take-home pay doesn’t fall by the full proportion of your salary, because your Personal Allowance of £12,570 and the National Insurance primary threshold stay the same whatever hours you work. A larger share of a part-time salary is tax-free.

Holiday for part-time workers

Most workers are entitled to paid holiday each year. For part-time workers, the statutory minimum is worked out in proportion to the days or hours you work. If your employer gives full-time staff more than the statutory minimum, you should normally get the same pro-rata share. GOV.UK’s holiday entitlement guide explains how to calculate it, and HMRC treats holiday pay as normal pay for tax.

Bank holidays can be a source of confusion. If your employer counts bank holidays as part of everyone’s entitlement, part-time workers should get a pro-rata share, even if they don’t normally work on the days bank holidays fall.

Pro-rata pay and the minimum wage

Your pro-rata pay must still work out at least the National Minimum Wage or National Living Wage for the hours you work. If a full-time salary is close to the minimum, check the hourly equivalent. Our guide to minimum wage rates has the current rates.

Pension, benefits and student loans

Some benefits are pro rata and some aren’t:

• Employer pension contributions are usually a percentage of your actual pay, so they fall in proportion. If your pay is low, check whether you meet the earnings trigger for automatic enrolment of £10,000 a year. You can still ask to join if you earn less.
• Benefits in kind, such as private medical insurance, may or may not be reduced.
• Student loan repayments are based on your actual pay, so a lower salary means smaller repayments, or none if you’re below your plan’s threshold. See our guide to student loans.

Term-time and annualised hours

Some jobs, especially in schools, are paid pro rata for term-time working. Your salary is the full-time salary reduced in proportion to the weeks you work, including your paid holiday, as well as the hours you work each week. Pay is usually spread evenly over twelve months, so you’re paid in school holidays too. Other employers use annualised hours, where you work an agreed number of hours across the year, sometimes more in busy periods and fewer in quieter ones, but receive the same salary each month.

Part-time work and a second job

If you work part-time for two employers, each job’s pay is treated separately for National Insurance and student loans, and HMRC uses tax codes to share out your allowance. Our guide to paying tax on two jobs explains how codes are allocated, and the two jobs tax calculator shows your take-home pay from both.

Changing your hours

If you’re thinking of reducing your hours, for example after parental leave, it’s worth comparing take-home pay at different hours rather than just the gross salary. Because the tax-free allowance stays the same, cutting your hours by a fifth usually reduces your take-home pay by less than a fifth. You have the right to request flexible working from your employer, and they must consider the request reasonably.

Calculate your pro-rata salary

Use our pro-rata salary calculator to work out your salary and take-home pay from the full-time salary, the full-time hours and your own hours or days. If you know the monthly take-home you need, the reverse salary calculator works back to the gross salary, and you can then see how many hours that would mean at a given rate. Your payslip should show your pro-rata salary as basic pay; our guide to reading your payslip explains the other lines.