What pro rata salary means

“Pro rata” on a job advert means the salary shown is what you would earn working full-time, and you will be paid a proportion of it that matches your actual hours or weeks. A band 4 NHS post advertised at £28,392 pro rata for 22.5 hours a week pays £17,035.20 a year, because 22.5 hours is 60 per cent of the NHS full-time week of 37.5 hours. The hourly rate stays the same and only the total changes.

The basic sum

Divide your contracted hours by the employer’s full-time hours, then multiply by the full-time salary.

Pro rata salary = full-time salary × (your hours ÷ full-time hours)

The full-time week differs between employers, so check it first:

• NHS Agenda for Change: 37.5 hours.
• Councils and school support staff on NJC terms: 37 hours.
• Civil Service: set by each department, and sometimes different in London, so check the advert.
• Teachers: no hours figure. Part-time teachers are paid a proportion based on the timetable or directed time.

The wrong denominator gives the wrong answer. Fifteen hours of a 37-hour job is a bigger share than fifteen hours of a 37.5-hour job.

Worked example: an NHS part-time post

Say you are offered a band 5 post at 22.5 hours a week. Band 5 starts at £32,073 in England from 1 April 2026.

£32,073 × (22.5 ÷ 37.5) = £32,073 × 0.6 = £19,243.80 a year.

If the advert also mentions a High Cost Area Supplement for London, that is pro rata too.

Worked example: a council job on the NJC spine

Say a council advertises a post at SCP 10, which is £28,608 for 2026/27, at 25 hours a week.

£28,608 × (25 ÷ 37) = £19,329.73 a year.

Worked example: term-time only school support staff

School support jobs often carry two reductions, fewer hours a week and fewer weeks a year. The weeks part follows the NJC model for term-time only staff, which pays you for the weeks you work plus a proportion of paid holiday, then spreads the total over 12 monthly payments.

In the NJC’s own example, a 39-week post comes out at 86.778 per cent of the full-time salary before any reduction for hours. Say a teaching assistant post is on SCP 5 (£26,427) for 30 hours a week over 39 weeks:

1. Weeks: £26,427 × 86.778% = £22,932.82.
2. Hours: £22,932.82 × (30 ÷ 37) = £18,594.18 a year.

The exact weeks percentage depends on the school’s leave year and your holiday entitlement, so two schools can give slightly different answers. Our guide to term-time only pay shows the full workings.

What else is pro rata

Most pay-related entitlements follow the same proportion. NHS staff get 27 days plus 8 public holidays full-time on appointment, so someone on 60 per cent of full-time hours gets 60 per cent of that. Allowances tied to the job, such as a teacher’s TLR, are normally paid at the same proportion as your contract.

A few things are not reduced in proportion. Unsocial hours enhancements are paid on the hours you actually work in the qualifying times. Overtime for part-time staff often starts only after you exceed full-time hours, with extra hours below that paid at plain time. NHS and council terms both have rules on this, so check the contract.

Pension and tax on pro rata pay

Public sector pension contribution rates usually work on actual pay, not the full-time equivalent. In the NHS Pension Scheme from April 2026, £19,243.80 falls in the 6.5 per cent tier, while the full-time band 5 salary of £32,073 would be in the 8.3 per cent tier. The Teachers’ Pension Scheme and the LGPS also set the rate by actual pensionable pay.

Lower pay can also mean less income tax and National Insurance, as more of it sits under the £12,570 Personal Allowance. The take-home pay calculator works out the monthly figure, and take-home pay for part-time workers explains why your net pay does not fall by exactly the same percentage as your gross pay.

Checking the figure in an offer

The offer letter should state both the full-time equivalent salary and your actual salary. If it gives only one, ask which. A quick check: divide the actual salary by your weekly hours and by 52.143, and compare that hourly rate with the full-time salary divided by full-time hours and 52.143. They should match. The guide to FTE salary vs actual salary explains the wording employers use.