One of the most persistent myths in UK employment is that part-time workers get a worse maternity deal. The truth is more reassuring: statutory maternity pay is calculated from your actual earnings, and the 90%-of-earnings rule means part-timers often get a better relative deal than full-timers in the early weeks. This guide explains exactly how maternity pay pro rata salaries work, who’s eligible, and what you’ll receive — with worked examples for typical part-time patterns.
The Two Big Myths About Part-Time Maternity Pay
Myth 1: “Maternity pay is pro-rated, so I’ll get less.” Statutory Maternity Pay (SMP) isn’t pro-rated. It’s calculated from your average weekly earnings — whatever they actually are. A part-timer earning £250 a week and a full-timer earning £600 a week both get 90% of their own earnings for the first six weeks.
Myth 2: “You need to work full-time to qualify.” There’s no hours requirement at all. The tests are about length of service and earnings level, not hours. Plenty of part-timers qualify comfortably; plenty of full-timers on very low hours… well, the earnings test is the one that matters, as we’ll see.
Do You Qualify? The Two Tests
To get SMP from your employer, you must pass both of these:
Test 1 — Continuous employment. You’ve worked for your employer continuously for at least 26 weeks by the end of the 15th week before your expected week of childbirth (the “qualifying week”). Part-time weeks count exactly the same as full-time weeks — a 16-hour week is a week of continuous employment, full stop.
Test 2 — Average earnings. Your average weekly earnings in the 8 weeks (or 2 months, for monthly-paid staff) ending with the last pay day before the qualifying week must be at least the Lower Earnings Limit: £125 a week.
That £125 threshold is the main hurdle for part-timers. Here’s how common patterns fare:
| Pattern | Weekly earnings | Meets £125? |
|---|---|---|
| 8 hrs × £12.21 | £97.68 | No |
| 10 hrs × £12.50 | £125.00 | Yes — exactly on the line |
| 12 hrs × £12.21 | £146.52 | Yes |
| 16 hrs × £13.00 | £208.00 | Yes |
| 22.5 hrs × £14.00 | £315.00 | Yes |
| 30 hrs × £12.21 | £366.30 | Yes |
Note the 10-hour row: £125.00 exactly meets the threshold (“at least” £125). But it’s knife-edge — one unpaid sick day in the relevant 8 weeks could tip you under. If your hours are irregular, the average is what counts, and overtime in those 8 weeks helps. Not sure what your average weekly earnings work out at? The free pro rata salary calculator converts your hours and hourly rate into a weekly figure in seconds.
If you don’t qualify for SMP, you may be able to claim Maternity Allowance from the government instead — £187.18 a week (or 90% of average earnings if lower) for up to 39 weeks, with its own eligibility rules. It’s worth less hassle than it sounds; many part-timers who miss SMP on the earnings test qualify for it.
How Much SMP You’ll Get: The Two Rates
SMP runs for up to 39 weeks and has two phases:
- Weeks 1–6: 90% of your average weekly earnings, with no cap. This is where part-timers do proportionally well.
- Weeks 7–39: the flat rate of £187.18 a week (from April 2025), or 90% of your average weekly earnings if that’s lower.
That second phase contains a subtle sting for part-timers: if 90% of your earnings is below £187.18, you get 90% for the whole 39 weeks — you never reach the flat rate.
Worked example — 20 hrs/week at £13/hr (£260/week average):
- Weeks 1–6: 90% × £260 = £234.00/week → £1,404 total
- Weeks 7–39: the lower of £187.18 and £234.00, so £187.18/week → 33 × £187.18 = £6,176.94
- Total SMP: £1,404 + £6,176.94 = £7,580.94
Worked example — 14 hrs/week at £12.50/hr (£175/week average):
- Weeks 1–6: 90% × £175 = £157.50/week → £945 total
- Weeks 7–39: the lower of £187.18 and £157.50 = £157.50/week → 33 × £157.50 = £5,197.50
- Total: £6,142.50
Notice the second worker gets 90% of her pay for all 39 weeks — her SMP replaces a larger share of her income than the higher earner’s does. The system is, perhaps unintentionally, quite progressive for part-timers who clear the eligibility threshold.
Occupational Maternity Pay: Where Pro Rata Really Bites
Statutory pay is only the floor. Many employers — the NHS, local government, universities, larger companies — offer occupational maternity schemes that are far more generous. And these are usually expressed in terms of your actual salary, which means part-timers get proportionally less in cash terms.
A typical NHS-style scheme: 8 weeks full pay, 18 weeks half pay plus SMP, then 13 weeks SMP only. For a part-timer, “full pay” means her full pay.
Worked example — NHS Band 5, 0.6 FTE, £17,982 actual salary (£345.81/week):
- Weeks 1–8 (full pay): £345.81/week → £2,766.48
- Weeks 9–26 (half pay + SMP): half pay = £172.91/week; SMP weeks 9–26 fall in the flat-rate phase. Her 90% figure is £311.23, so she gets the £187.18 flat rate. Combined: £172.91 + £187.18 = £360.09/week → 18 × £360.09 = £6,481.62. (Employers offset SMP against occupational pay; the total can’t normally exceed full pay — here £360.09 slightly exceeds £345.81, so it would typically be capped at £345.81. Always check your employer’s policy.)
- Weeks 27–39 (SMP only): 13 × £187.18 = £2,433.34
The exact offset rules vary by employer, so treat this as illustrative and check your maternity policy. The key point stands: occupational schemes multiply your salary, so the cash amounts scale with your hours even though the structure is identical to full-timers’.
Keeping in Touch Days and Your Pension
Two practical points part-timers often miss:
Keeping in Touch (KIT) days. You can work up to 10 KIT days during maternity leave without ending it. You’re paid for these — usually at your normal hourly rate — and they’re a good way to ease back in. Your employer can’t require them, and you can’t be penalised for declining.
Pension contributions. During paid maternity leave, you contribute based on the pay you actually receive, but your employer must contribute as if you were on full normal pay. For NHS pension members, that means the employer’s 14.38% keeps flowing on your full WTE-adjusted salary. During unpaid leave, neither side contributes unless you arrange otherwise. This is genuinely valuable — don’t overlook it.
Returning to Work: Your Rights
- You have the right to return to the same job after Ordinary Maternity Leave (26 weeks) on the same terms — including your part-time hours.
- After Additional Maternity Leave (up to 52 weeks total), you’re entitled to return to the same job or a suitable alternative on no less favourable terms.
- You can request flexible working on return — including keeping or adjusting part-time hours — and your employer must handle the request reasonably.
- Your continuity of employment is preserved throughout maternity leave, which matters for redundancy rights, notice periods and future maternity eligibility.
If your employer suggests your part-time role “isn’t available any more” while you’re on leave, take advice — this is one of the most common forms of maternity discrimination, and the law is firmly on your side.
What About Partners? Paternity and Shared Parental Pay
Partners get their own entitlements, calculated the same way from actual earnings:
- Statutory Paternity Pay: £187.18/week (or 90% of earnings if lower) for 1–2 weeks, with the same £125 earnings threshold and 26-week service test.
- Shared Parental Leave/Pay: if the mother curtails her maternity leave, up to 50 weeks of leave and 37 weeks of pay can be shared. ShPP is paid at the flat £187.18/90% rate. For part-time families, sharing can be financially smart — the lower-earning partner taking leave costs the household less in lost income.
FAQs
Do you get full maternity pay if you work part-time?
Statutory Maternity Pay is based on your actual average weekly earnings, not pro-rated down from a full-time figure — so in that sense, yes, you get the “full” calculation. What scales with your hours is the cash amount, because 90% of £200 is less than 90% of £600. Occupational schemes pay your actual salary’s fractions, so those are effectively pro-rated.
What if I earn less than £125 a week?
You won’t qualify for SMP from your employer, but you may qualify for Maternity Allowance (£187.18/week or 90% of earnings if lower, for up to 39 weeks). The MA earnings test is lower — you need average earnings of at least £30 a week over any 13 weeks in the 66 weeks before your due date. Many very-part-time workers qualify for MA even when SMP is out of reach.
Does overtime count toward the £125 earnings threshold?
Yes — the 8-week relevant period uses your gross earnings including overtime, bonuses and commission. If your contracted hours alone fall short, a few overtime shifts in the right window can push you over. Keep payslips from that period.
Can I be made redundant while on maternity leave?
You can be selected for redundancy, but from 6 April 2024 the protection is stronger: if you’re pregnant or on maternity leave (up to 18 months from birth), you must be offered any suitable alternative vacancy ahead of other candidates. Part-time status doesn’t weaken this right. If it happens to you, get advice quickly — tribunal time limits are short.
The Bottom Line
Maternity pay is one of the fairer corners of employment law for part-timers: no hours threshold, earnings-based calculation, and the 90% rule means the system replaces a bigger share of a modest part-time wage than a large full-time one. The £125 weekly earnings test is the gate to watch — clear it, and the rest follows. To check where your earnings sit, run your hours through our free pro rata salary calculator — and for anything pay-related after the baby arrives, it’ll be there too.