Maternity leave date calculator
Maternity law runs on the expected week of childbirth (EWC) — the Sunday-to-Saturday week containing your due date. Every deadline counts back from it. Enter your due date and get the full timetable.
Statutory maternity leave
2026/2752 weeks — start from 11 weeks before the due week
26 weeks ordinary + 26 weeks additional. 39 weeks are paid (if eligible for SMP). Minimum 2 weeks must be taken after birth — 4 if you work in a factory.
The dates, decoded
- Qualifying week — the 15th week before the EWC. Your SMP eligibility (26 weeks' service, earnings test) is measured here, and by the end of it you must tell your employer you're pregnant, the EWC, and your intended start date.
- Earliest leave start — 11 weeks before the EWC. Leave also starts automatically if the baby arrives early or you're off with a pregnancy-related illness in the final 4 weeks.
- SMP end — 39 weeks after your leave starts. The remaining 13 weeks of leave are unpaid.
- Latest return — 52 weeks after leave starts. Give 8 weeks' notice to return earlier.
Common questions
When do most people actually start maternity leave?
Between 2 and 4 weeks before the due date is most common — later starts keep more paid weeks for after the birth. The legal window is anywhere from 11 weeks before the EWC to the birth itself.
What if the baby comes before my planned start date?
Leave (and SMP) start automatically the day after the birth. Your other dates shift accordingly; the qualifying-week test uses the original EWC.
Can I change my chosen start date?
Yes — give your employer 28 days' notice of the new date where reasonably practicable.
Sources for the figures on this page
Last checked 3 July 2026How we keep these current: methodology & update policy.