UK Pro-Rata Salary Calculator
Work out a part-time salary from a full-time equivalent (FTE). Enter the full-time figure plus your hours, days, or FTE % — we'll show pro-rated income tax, NI, student loan, and pension so you see take-home side-by-side against full-time.
Pro-Rated Annual Salary
£36,00030 / 37.5 hours per week (80% FTE)
Pro-Rated Take-Home (annual)
£29,440£2,453 / month
Net vs FT Net
81.96%Gross ratio: 80.00%
| Item | Full-Time | Pro-Rated | Difference |
|---|---|---|---|
| Gross Salary | £45,000 | £36,000 | -£9,000 |
| Income Tax | £6,486 | £4,686 | -£1,800 |
| National Insurance | £2,594 | £1,874 | -£720 |
| Student Loan | £0 | £0 | £0 |
| Pension | £0 | £0 | £0 |
| Take-Home Pay (annual) | £35,920 | £29,440 | -£6,480 |
| Monthly Take-Home | £2,993 | £2,453 | -£540 |
| Weekly Take-Home | £691 | £566 | -£125 |
Why pro-rata net ≠ pro-rata gross
Personal Allowance is flat
Everyone gets the first £12,570 tax-free. A part-time salary uses a bigger proportion of this allowance, pulling your effective tax rate down.
Progressive bands
Going part-time can drop you out of the 40% higher-rate or 60% effective band (where PA tapers). Net can fall by much less than 20–30%.
NI primary threshold
NI isn't charged until £12,570. A low-FTE part-time role can be under the threshold entirely — zero employee NI.
Student loan thresholds
Plan 1/2/4/5 all have their own thresholds. Pro-rated income may fall under the threshold for plans with high cut-offs (Plan 4 at £33,795), saving 9% of the excess.
Part-time take-home on a £45,000 full-time salary (2026/27)
England/Wales/NI, no student loan or pension. Notice the right-hand column: at 50% FTE your gross halves, but your take-home is well above half the full-time net — the flat £12,570 Personal Allowance and the NI threshold do more of the work as your salary falls.
| FTE | Pro-rated gross | Take-home (annual) | % of full-time net |
|---|---|---|---|
| 100% (full-time) | £45,000 | £35,920 | 100.0% |
| 80% | £36,000 | £29,440 | 82.0% |
| 60% | £27,000 | £22,960 | 63.9% |
| 50% | £22,500 | £19,720 | 54.9% |
| 40% | £18,000 | £16,480 | 45.9% |
Figures are engine-computed for 2026/27; income tax and NI thresholds are unchanged from 2025/26.
Worked example
£40,000 full-time job, working 30 of 37.5 hours
FTE = 30 ÷ 37.5 = 80%, so the pro-rated salary is £40,000 × 0.8 = £32,000. Full-time take-home would be £32,320; the part-time take-home is £26,560 — that's 82.2% of the full-time net for 80% of the hours, because the £12,570 allowance is unchanged.
Working part-time on the NHS Agenda for Change scales specifically? The NHS Pay Calculator pro-rates your exact band and pay point against the 37.5-hour AfC full-time week, including HCAS and NHS Pension Scheme tiered contributions.
Student loan repayment thresholds (2026/27)
You repay a fixed percentage of everything you earn above your plan's annual threshold. Dropping below the threshold when you go part-time stops the deduction entirely.
| Plan | Annual threshold | Rate |
|---|---|---|
| Plan 1 | £26,900 | 9% |
| Plan 2 | £29,385 | 9% |
| Plan 4 (Scotland) | £33,795 | 9% |
| Plan 5 | £25,000 | 9% |
| Postgraduate Loan | £21,000 | 6% |
Frequently asked questions
How do I calculate a pro-rata salary?
Pro-rata salary = full-time equivalent (FTE) salary × your FTE ratio. If a job advertises £40,000 FTE and you'll work 30 hours against a 37.5-hour full-time week, your FTE is 30/37.5 = 0.8 (80%), so your pro-rata salary is £40,000 × 0.8 = £32,000.
Does pro-rata affect my tax and take-home pay?
Yes, but not proportionally. Because UK income tax is progressive and everyone gets the same £12,570 Personal Allowance, a part-time salary is taxed at lower average rates than the full-time equivalent. Your net pay usually falls by less than your gross salary in percentage terms.
What counts as full-time hours in the UK?
There is no statutory UK definition, but 35 to 40 hours per week is typical, with 37.5 hours being the most common for office-based roles. Check your employer's standard full-time hours when calculating your FTE ratio — NHS Agenda for Change uses 37.5, many law firms use 35, and retail often uses 40.
Should pension contribution percentage stay the same when going part-time?
Usually yes — most workplace pensions apply the contribution as a percentage of your actual (pro-rated) salary. So a 5% contribution still means 5%, but the cash amount scales down with your salary.
Does going part-time change my National Insurance?
Employee NI has a £12,570/year primary threshold — you only pay NI on earnings above that. If your pro-rated salary falls below the threshold (or close to it), you may pay little or no NI despite earning a meaningful salary.
How do I convert days per week to an FTE ratio?
Divide your working days by the full-time days. A 4-day week against a 5-day full-time week is 4/5 = 0.8 (80% FTE); a 3-day week is 3/5 = 0.6 (60%). Switch the calculator's 'Ratio Basis' to 'Days per week' to work it out automatically, including non-standard full-time patterns.
Is my holiday entitlement also pro-rated?
Yes. Statutory holiday is 5.6 weeks of your normal working week, so a part-timer accrues the same 5.6 weeks but in fewer days. A full-timer on a 5-day week gets 28 days; a 3-day-week part-timer gets 5.6 × 3 = 16.8 days. Pay during holiday is at your pro-rated rate.
Does a student loan still get deducted on a part-time salary?
Only if your pro-rated salary is above your plan's annual threshold. For 2026/27 the thresholds are Plan 1 £26,900, Plan 2 £29,385, Plan 4 £33,795, Plan 5 £25,000 and Postgraduate £21,000. Going part-time can drop you under a threshold and stop the 9% (or 6% postgraduate) deduction entirely.
Related Calculators
Take-Home Pay Calculator
UK salary calculator — net pay after PAYE, NI, student loan and pension, month-by-month with Scottish band support.
UK Salary Converter
Convert between annual, monthly, weekly and hourly UK salary with HMRC 2026/27 and 2025/26 rates. See gross and take-home pay after tax and NI.
Income Tax Calculator
Run your salary through 2025-26 and 2026-27 UK tax bands with personal allowance, taper and reliefs applied — including Scottish 6-band rates.
National Insurance Calculator
Class 1 employee NI 8% main / 2% upper, plus employer NIC liability — current PT/UEL thresholds applied.
Holiday Pay Calculator
12.07% rolled-up holiday pay for variable-hour and zero-hours workers — 5.6 weeks statutory entitlement applied.