Pro Rata Salary Calculator
Updated August 2026 · Free · No sign-up
Convert a full-time salary to pro rata pay for part-time hours or days — with monthly, weekly, and hourly equivalents, pro-rated holiday, and what to check before accepting a part-time offer.
Quick answer: Pro rata salary = FTE salary × (your weekly hours ÷ full-time hours). A £30,000 FTE role at 3 days a week (0.6 FTE) pays £18,000 — £1,500/month. The hourly rate stays identical; only the volume of hours changes.
Pro Rata: The Formula
Pro Rata Salary = FTE Salary × (Your Hours ÷ Full-Time Hours)
"Pro rata" simply means proportional: you earn the same hourly rate as a full-timer, for fewer hours. Job adverts quote the FTE salary ("£30,000 pro rata") — your actual pay is the fraction. The same fraction cascades through everything salary-linked: holiday entitlement, pension contributions, bonus targets, and sick-pay schemes.
Worked Examples
Example 1 — 3 days a week. £30,000 FTE, 3 of 5 days (0.6 FTE): £18,000 — £1,500/month, £346/week. Holiday: 3 × 5.6 = 16.8 days.
Example 2 — hours basis. $52,000 FTE at 25 of 40 hours (0.625): $32,500; the hourly rate — $25 — matches the full-timer exactly.
Example 3 — the advert decode. "Salary £24,000 pro rata, 22.5 hrs/week (FT 37.5)": actual pay 24,000 × 0.6 = £14,400. Adverts rarely do this multiplication for you — always ask which number lands in your bank.
Common FTE Fractions
| Pattern (of 5-day/37.5h week) | FTE | £30,000 becomes | Holiday days |
|---|---|---|---|
| 4 days / 30 hrs | 0.8 | £24,000 | 22.4 |
| 3 days / 22.5 hrs | 0.6 | £18,000 | 16.8 |
| 2.5 days / 18.75 hrs | 0.5 | £15,000 | 14 |
| 2 days / 15 hrs | 0.4 | £12,000 | 11.2 |
What Else Goes Pro Rata (and What Doesn't)
- Pro rata: salary, holiday entitlement (calculator), employer pension contributions, bonuses (usually), sick-pay scheme weeks.
- Not pro rata: your hourly rate (identical by definition), statutory payments with flat rates (SSP weekly rate is the same if you qualify — see the SSP calculator), most benefits-in-kind (insurance is rarely 0.6 of a policy), and fixed allowances unless stated.
- Watch UK tax: part-time pay uses the same personal allowance (£12,570) — a 0.5 FTE role is taxed lightly, so take-home falls less than 50% vs full-time. Pro rata gross ≠ pro rata net.
Negotiating Part-Time: The Checks
- Confirm the FTE basis in writing — "£30k pro rata" against a 37.5-hour FTE differs from a 40-hour FTE by 6%.
- Workload pro rata, not just pay: the classic part-time trap is 100% of the job at 60% of the salary. Objectives should scale with the fraction.
- Meeting patterns: if the team's rituals fall on your off-days, you'll attend unpaid or miss decisions — fix the calendar before signing.
- Progression parity: UK part-time workers have statutory protection against less-favourable treatment — promotion criteria and pay reviews must not quietly require full-time.
Pro Rata vs Prorated vs Term-Time
Same Latin, three payroll meanings: pro rata (this page) = ongoing part-time fraction of an FTE salary; prorated salary = a one-off partial-period payment for joining/leaving mid-month (that calculator); term-time only = working school weeks with pay annualised over 12 months — the most complex variant, with its own calculator. Comparing a part-time offer against hourly work? Convert both directions with the salary↔hourly tools.
Frequently Asked Questions
What does pro rata salary mean?
The proportional share of a full-time salary for part-time hours: FTE salary × your hours ÷ full-time hours. The hourly rate matches a full-timer — you just work fewer hours.
How do I calculate pro rata salary for 3 days a week?
FTE salary × 3/5. £30,000 becomes £18,000 (£1,500/month). Holiday follows the same fraction: 16.8 statutory days.
What is £25,000 pro rata for 20 hours?
Against a 37.5-hour full-time week: 25,000 × 20/37.5 = £13,333. Against a 40-hour FTE: £12,500 — always confirm the FTE basis.
Is holiday entitlement pro rata too?
Yes — days per week × 5.6 handles it automatically: 3 days/week gives 16.8 days. Bank-holiday treatment for part-timers should be pro-rated fairly within that total.
Does pro rata affect my hourly rate?
No — equal hourly rates are the point (and, in the UK, a legal protection). If the implied hourly rate is lower than a full-timer's, the offer is not truly pro rata.
Is tax pro rata for part-time work?
Tax bands don't scale down — the same personal allowance applies, so part-time take-home falls proportionally LESS than gross. A 0.5 FTE salary often nets 55-60% of full-time take-home.
What is 0.6 FTE in hours?
22.5 hours against a 37.5-hour week, or 24 against 40. Confirm which full-time definition your employer uses.
Are bonuses and pensions pro rata?
Usually: bonus targets scale to the fraction, and percentage-based pension contributions apply to your actual salary. Flat-value benefits (insurance, allowances) often stay whole — check each.
What should a pro rata offer letter state?
The FTE salary, the FTE hours basis, your hours/days, the resulting actual salary, and pro-rated holiday. Missing any of the five invites a payroll dispute later.
How is pro rata different from prorated?
Pro rata is an ongoing part-time fraction; prorated is a one-off partial-month calculation for starters, leavers, or unpaid days.
✓ Formula verified • Last updated: August 20, 2026