Maternity Leave Date Calculator
Map every key UK maternity date from your baby's due date
Last updated: June 2026
Maternity Leave Date Calculator
Enter your baby's due date to map out every key maternity date: your qualifying week, the earliest your leave can start, your notice deadline, and when your Statutory Maternity Pay (SMP) and 52 weeks of leave run out.
What this maternity leave date calculator does
Working out your maternity dates by hand is fiddly because UK rules count backwards from your expected week of childbirth (EWC) — the Sunday-to-Saturday week your due date falls in — rather than from the due date itself. This planner takes the date on your MATB1 certificate and instantly maps the dates that matter: your qualifying week (the 15th week before the EWC), the deadline to tell your employer (at least 15 weeks before your due date), the earliest your leave can start (11 weeks before the EWC), the 8-week period used to work out your average earnings, and the dates your Statutory Maternity Pay (SMP) and your full 52 weeks of leave end.
It's built for expectant parents in England, Scotland and Wales who want a clear, dated checklist — whether you're deciding when to stop work, checking you'll meet the notice deadline, or planning the household budget around the 39 paid weeks and the unpaid stretch that follows. Every date is calculated live in your browser; nothing is stored or sent anywhere.
How it works
- Find the EWC. Your due date is converted to the Sunday-to-Saturday week it lands in. All the statutory milestones are measured from the Sunday that starts this week.
- Count back 15 weeks to find the qualifying week. You must have at least 26 weeks' continuous service with your employer by this week to qualify for SMP, and you must notify your employer by the end of it.
- Count back 11 weeks to find the earliest your leave can begin.
- Apply your chosen start date. Leave (and usually SMP) runs from the day you stop work. The calculator then adds 6 weeks (paid at 90% of earnings), 39 weeks (the end of SMP) and 52 weeks (the end of your leave entitlement).
Two automatic triggers can override your plan: if your baby arrives early, your leave starts the day after the birth; and if you're off with a pregnancy-related illness in the 4 weeks before the EWC, your leave starts automatically.
Worked example
Suppose your due date is Wednesday 1 July 2026. That date falls in the week beginning Sunday 28 June 2026, so the EWC starts on 28 June 2026.
- Qualifying week: 15 weeks before 28 June 2026 → week beginning Sunday 15 March 2026.
- Notify employer by: Saturday 21 March 2026 (the end of the qualifying week).
- Earliest leave start: 11 weeks before 28 June 2026 → Sunday 12 April 2026.
- If you start leave on your due date (1 July 2026): the first 6 weeks of SMP (at 90% of pay) run to 11 August 2026; your 39 weeks of SMP end on 30 March 2027; and your full 52-week leave ends on 29 June 2027.
During the 39 SMP weeks you receive 90% of your average weekly earnings for the first 6 weeks, then the lower of £194.32 a week or 90% of your earnings for the remaining 33 weeks. The final 13 weeks of leave (weeks 40–52) are usually unpaid.
Frequently asked questions
When is the earliest I can start maternity leave?
The earliest you can normally start statutory maternity leave is 11 weeks before the expected week of childbirth (the Sunday-to-Saturday week your due date falls in). You can choose to work right up to the birth if you prefer.
By when must I tell my employer I'm taking maternity leave?
You must tell your employer at least 15 weeks before your due date — that is, by the end of the qualifying week (the 15th week before the expected week of childbirth). You can change your start date later by giving 28 days' notice.
How long is maternity leave and how much of it is paid?
Statutory maternity leave is 52 weeks: 26 weeks of ordinary leave followed by 26 weeks of additional leave. Statutory Maternity Pay covers up to 39 of those weeks — 6 weeks at 90% of your average earnings, then 33 weeks at the lower of £194.32 or 90% of earnings. The remaining 13 weeks are usually unpaid.
What happens if my baby comes early?
If your baby is born before your planned leave start date, your maternity leave starts automatically the day after the birth. Your leave can also start automatically if you're off work with a pregnancy-related illness in the 4 weeks before the expected week of childbirth.
Source: rules and rates verified against GOV.UK — Maternity pay and leave (GOV.UK). Figures are for guidance only; check your own circumstances with your employer or HR.