Pro rata salary calculator

Work out what a full-time salary pays for part-time hours or days: your pro rata salary, monthly and weekly pay, hourly rate and holiday.

How this calculator works

Pro rata means "in proportion". A part-time job advertised at a full-time salary pays you the same share of that salary as the share of full-time hours you work.

• Your share = your hours ÷ full-time hours (or your days ÷ full-time days). 22.5 hours out of 37.5 is 0.6, often written as 0.6 FTE (full-time equivalent).
• Pro rata salary = full-time salary × your share. £30,000 × 0.6 is £18,000 a year.
• Monthly and weekly pay = the yearly salary ÷ 12 or ÷ 52, before tax.
• Hourly rate = full-time salary ÷ (full-time hours × 52). It's the same for you as for a full-time worker, which is the point of pro rata pay: £30,000 for 37.5 hours a week is £15.38 an hour. Working by days, it shows the daily rate instead.
• Holiday = full-time holiday × your share. The legal minimum is 5.6 weeks a year: 5.6 × the days you work a week, up to 28 days, which can include bank holidays.

The figures are before tax. To see what you'll actually be paid after Income Tax, National Insurance, pension and student loan, put your pro rata salary into the take-home pay calculator.

Tips for part-time pay

• Check the full-time hours. Pro rata salaries depend on what the employer counts as full time, often 35, 37.5 or 40 hours. The same advertised salary pays a different hourly rate on each.
• Ask whether holiday includes bank holidays. Part-time workers should get bank holidays pro rata too. If you don't work Mondays you might miss most bank holidays, so a fair employer gives you the hours as extra leave.
• Check the minimum wage. From 1 April 2026 the National Living Wage is £12.71 an hour for anyone aged 21 and over. Your hourly rate can't be lower.
• Part-time workers have the same rights. By law you can't be treated less favourably than a comparable full-time worker, so your pay rate, pension and holiday should all be pro rata.
• Irregular hours or a mid-year start? The holiday entitlement calculator handles irregular hours, starting and leaving part way through the year, and bank holidays.

Frequently asked questions

What does "£30,000 pro rata" mean?

It means £30,000 is the salary for full-time hours, and you'll be paid a share of it based on the hours you work. On 22.5 hours a week against a full-time 37.5, you'd get 60%, which is £18,000 a year.

How do I work out a pro rata salary?

Divide your hours by the full-time hours, then multiply the full-time salary by the answer. For 3 days a week against 5, that's 3 ÷ 5 = 0.6, and 0.6 × £30,000 = £18,000.

Should I use hours or days?

Use whatever your contract uses. If your days are shorter or longer than a full-time day, use hours, because that's what your pay is based on. Days a week is simpler if you work full days.

How much holiday do part-time workers get?

At least 5.6 weeks, the same as full-time workers, but in proportion to your working week. On 3 days a week that's 5.6 × 3 = 16.8 days, including any bank holidays. If your employer gives full-time staff more than the minimum, you should get the same share of that.

Is the pro rata salary before or after tax?

Before tax. Part-time pay often falls under the £12,570 Personal Allowance or the National Insurance threshold, so you may pay little or no tax. The take-home pay calculator shows exactly what you'd get.

Is this financial advice?

No. It's an estimate to help you understand a job offer. Your contract sets your actual pay, and things like overtime, shift allowances or unpaid breaks can change it.

Results are estimates for illustration only and aren't financial advice. National Living Wage from GOV.UK, checked 6 November 2026.