September 2026

We Built a Free Pro Rata Calculator: Here's the Story

Part-time salary maths confuses everyone. Here's why we built a free tool that turns any FTE salary into exact part-time pay — plus what pro rata really means.

12 September 2026 · Money Meister · 9 min read

If you've been job hunting in the UK, you've seen salaries advertised as '£40,000 pro rata'. It appears on job adverts for part-time roles, school-term positions, and job shares. But what does it actually mean for your take-home pay? And how do you work out what you'll really earn? Use the free pro rata calculator → to skip straight to your exact figure.

In this guide, I'll explain everything you need to know about pro rata pay. You'll learn how to calculate it, what affects your final salary, and how to use the free Money Meister Pro Rata Salary Calculator to get an instant figure with full tax deductions.

What Is Pro Rata Pay?

Pro rata comes from Latin, meaning 'in proportion'. In the context of salary, it means your pay is calculated proportionally based on how many hours you work compared to a full-time equivalent (FTE) role.

When an employer advertises a salary of '£50,000 pro rata', they are stating that the full-time salary for that position is £50,000. If you work part-time hours, your actual salary will be a proportion of that figure. A 0.6 FTE role (3 days per week in a standard 5-day workplace) would pay £30,000.

Pro rata arrangements are common across many sectors in the UK, particularly in education, healthcare, retail, and administrative roles. They allow employers to attract skilled professionals who want or need to work reduced hours, while ensuring fair pay relative to full-time colleagues.

How to Calculate Pro Rata Salary

The pro rata calculation is straightforward, but it's surprising how many people get it wrong or overestimate their take-home pay. Here's the formula:

The formula

Pro Rata Salary = FTE Salary x (Your Weekly Hours / FTE Weekly Hours)

Let's walk through an example to make it concrete.

Example 1: Three days per week

You've been offered a role with a £45,000 FTE salary. The standard working week is 37.5 hours (Monday to Friday, 9 to 5 with an hour lunch). You'll be working Monday, Tuesday, and Wednesday — 22.5 hours per week.

Step 1: Calculate your FTE ratio: 22.5 / 37.5 = 0.6 (60% FTE)

Step 2: Apply the ratio to the FTE salary: £45,000 x 0.6 = £27,000

Your pro rata annual salary is £27,000. That's £2,250 per month or £519 per week before any deductions for tax, National Insurance, or pension contributions.

Example 2: Four-day week

A popular flexible working pattern is the compressed four-day week. You work your full daily hours but only four days out of five.

FTE salary: £55,000. FTE hours: 37.5. Your hours: 30 (four days at 7.5 hours each).

FTE ratio: 30 / 37.5 = 0.8 (80% FTE). Pro rata salary: £55,000 x 0.8 = £44,000.

Example 3: Term-time only role

Term-time only contracts are common in schools and educational settings. You only work during school term weeks (typically 38-39 weeks per year) but may be paid in equal monthly instalments across 12 months.

FTE salary: £30,000. FTE hours: 37.5. Your hours: 22.5. Working weeks: 39 of 52.

Step 1: Calculate hours ratio: 22.5 / 37.5 = 0.6

Step 2: Calculate weeks ratio: 39 / 52 = 0.75

Step 3: Combined ratio: 0.6 x 0.75 = 0.45

Pro rata salary: £30,000 x 0.45 = £13,500

Using the Pro Rata Salary Calculator

Rather than working through these calculations manually, you can use the free Pro Rata Salary Calculator. It does the maths instantly and includes an optional tax breakdown so you can see exactly what your take-home pay would be.

The calculator lets you enter your FTE salary, the standard full-time hours for your role, and the hours you'll actually work. It then calculates your pro rata salary, hourly rate, and FTE percentage. If you toggle on 'Show take-home pay after tax', it uses current HMRC rates to calculate Income Tax, National Insurance, and student loan deductions based on your pro rata income.

You can adjust the tax year, select your region (England, Scotland, or Wales), add your pension contribution percentage, and enter your tax code for a precise calculation. The results update in real time as you change any field.

Does Pro Rata Pay Affect Your Hourly Rate?

This is one of the most common questions about pro rata pay, and the answer is straightforward: pro rata pay preserves your hourly rate. Your total salary is lower because you work fewer hours, but your rate per hour is exactly the same as someone doing the same job full-time.

To check whether a pro rata role offers fair value, divide the FTE salary by the annual full-time hours to find the hourly rate, then compare it to market rates for similar roles. The Money Meister calculator shows your hourly rate automatically in the results.

Benefits and Pro Rata Contracts

If you work on a pro rata basis, your employment rights and benefits are generally calculated in proportion to your hours. This includes:

Holiday entitlement: 5.6 weeks per year, calculated pro rata (if you work 3 days, you get 5.6 x 3 = 16.8 days)
Pension contributions: Employer and employee contributions are based on your actual pro rata earnings
Sick pay: Statutory Sick Pay (SSP) eligibility is based on your average earnings, not your FTE salary
Maternity and paternity pay: Calculated on your actual earnings, not the FTE figure

Some benefits, like private medical insurance or life assurance, may have a minimum hours threshold (often 22.5 hours per week). Always check your contract or employee handbook for the specific terms.

Common Pro Rata Scenarios

Job shares

Job sharing is when two or more people share one full-time role. Each person has a pro rata contract based on their share of the role. For example, a £60,000 FTE role shared 50/50 would mean each person earns £30,000 pro rata.

School and term-time hours

School support staff, catering workers, and some administrative roles follow term-time patterns. You're paid only for the weeks you work (typically 38-39 weeks), though many employers spread the pay across 12 equal monthly instalments to help with budgeting.

Reduced hours returning from parental leave

Many parents returning from maternity or paternity leave choose to reduce their hours. Employers generally calculate the pro rata salary based on your previous FTE salary and new hours, which can be a significant adjustment to household income.

Tax Implications of Pro Rata Pay

Your pro rata salary is taxed using the same progressive system as any other employment income. The tax-free personal allowance (£12,570 for 2026/27) does not change because you work part-time — it is applied to your actual earnings.

This means part-time workers often benefit from a lower effective tax rate. A pro rata salary of £24,000 would put you firmly in the basic rate band, with only 20% tax on earnings above the personal allowance. Your National Insurance contributions would also be lower, at just 8% on earnings between £12,570 and £24,000.

However, if you work multiple part-time roles, your total income across all roles is combined for tax purposes. This could push you into a higher tax bracket, even though each individual role appears modest. Always check your tax code carefully if you hold multiple jobs.

How to Negotiate a Pro Rata Role

When negotiating a pro rata role, focus on these key points:

Confirm the FTE salary is based on a standard week for that industry, not an inflated figure that makes the pro rata look generous
Clarify which benefits are pro rated and which have minimum hours thresholds
Ask about overtime rates if you're likely to work additional hours occasionally
Check whether the salary is reviewed annually against the same FTE benchmark
If it's a term-time role, confirm whether pay is spread across 12 months or paid during term-time only

Before going into negotiations, use the Pro Rata Salary Calculator to know exactly what salary figure you're aiming for. It's much harder for an employer to lowball you when you arrive with a clear number based on the published FTE salary.

Final Thoughts

Understanding pro rata pay is essential for anyone considering part-time work, job shares, or term-time roles. The calculation itself is simple, but the impact on your household budget, tax position, and benefits can be significant.

The Pro Rata Salary Calculator gives you an instant, accurate figure with full tax deductions calculated at current HMRC rates. Whether you're evaluating a job offer, planning a return to work after parental leave, or considering reduced hours, it takes the guesswork out of the numbers.

For more detailed information about how your salary is taxed, explore the UK Tax Calculator for a full breakdown of Income Tax, National Insurance, and student loan deductions across all tax bands.

Frequently Asked Questions

How do I calculate my pro rata salary?

Divide your actual weekly hours by the full-time hours for that role, then multiply the full-time salary by that ratio. For a £40,000 FTE role at 37.5 hours per week, working 22.5 hours (3 days) gives a ratio of 0.6 and a pro rata salary of £24,000.

What does pro rata mean in salary terms?

Pro rata means 'in proportion'. When a salary is advertised as 'pro rata', the advertised figure is the full-time equivalent (FTE) salary. Your actual pay is calculated proportionally based on the hours you work compared to a standard full-time week for that role.

Is pro rata pay the same hourly rate as full-time?

Yes. Pro rata pay preserves the same hourly rate as the full-time position. Your total annual salary is lower because you work fewer hours, but your rate per hour is identical to what a full-time colleague would earn in the same role.

What is the difference between FTE and pro rata?

FTE (Full-Time Equivalent) is the ratio of hours worked compared to full-time. A 1.0 FTE role is full-time. A 0.6 FTE role means you work 60% of full-time hours. Pro rata is the actual salary you receive based on your FTE ratio. They are two sides of the same calculation.

Do I get holiday pay on a pro rata contract?

Yes. Part-time workers are entitled to the same 5.6 weeks of paid holiday as full-time employees, calculated pro rata based on your working days. If you work 3 days per week, you'd get 5.6 x 3 = 16.8 days of holiday per year.

Sources: HMRC tax rates and personal allowance for 2026/27 (gov.uk). Employment rights guidance from ACAS and GOV.UK. All calculations based on standard UK employment law and HMRC tax rules. The Pro Rata Salary Calculator and other tools available on moneymeister.co.uk.