Maternity Leave Calculator UK
Enter the due date to see the expected week of childbirth, the qualifying week, the notice deadline, the earliest start date and when Statutory Maternity Pay ends. No signup needed.
Work out the maternity dates
Enter the due date from the MAT B1 certificate or the midwife. Add a planned start date to see pay and return dates for that plan.
Enter the due date first to see the earliest possible start.
Enter the baby’s due date to see the key maternity leave dates.
General guidance for employees in Great Britain, not legal advice. Eligibility for Statutory Maternity Pay depends on each employee’s circumstances. Check individual cases on GOV.UK.
Track this automatically in Leavely
Record the due date once and Leavely works out these dates for you, tracks KIT days, and keeps admin-only notes alongside the leave record.
How the maternity leave dates are worked out
Every maternity deadline counts back from one date: the start of the expected week of childbirth (EWC). The EWC is the week the baby is due, and it always starts on a Sunday. If the baby is due on a Wednesday, the EWC starts on the Sunday before.
- Find the EWC. Take the due date and go back to the Sunday of that week.
- Count back 15 weeks for the qualifying week. The 15th week before the EWC (Sunday to Saturday) is the qualifying week. The employee must tell you about the pregnancy, and when they want leave to start, by the end of it.
- Count back 11 weeks for the earliest start. Maternity leave cannot start before the 11th week before the EWC.
- Count back 4 weeks for automatic start. If the employee is off for a pregnancy-related reason from the 4th week before the EWC, maternity leave starts automatically the next day.
After the birth, the first 2 weeks are compulsory leave (4 weeks for factory workers). Maternity leave can last up to 52 weeks in total. If the baby arrives before the planned start, leave starts the day after the birth.
How Statutory Maternity Pay is structured
Statutory Maternity Pay (SMP) is paid for up to 39 weeks, counted from the first day of leave:
- First 6 weeks: 90% of the employee's average weekly earnings.
- Next 33 weeks: the statutory weekly rate, or 90% of average weekly earnings if that is lower.
The statutory weekly rate is set by the government each April, so this calculator does not show pound amounts. Check the current rate and eligibility rules on GOV.UK: maternity pay and leave. Any leave after the 39 weeks has no statutory pay, though your own policy may pay more.
Keeping-in-touch days
An employee on maternity leave can work up to 10 keeping-in-touch (KIT) days. They are useful for training or team days before the return to work. Keep a record of each one so you know how many are left.
Paternity leave for the partner
Paternity leave is 1 week or 2 weeks, taken together or as two separate weeks, within 52 weeks of the birth. The partner must give 28 days' notice before each period. Read more in our paternity leave guide. Parents who want to share the leave can look at shared parental leave.
Frequently asked questions
When is the earliest maternity leave can start?
Maternity leave cannot start before the 11th week before the expected week of childbirth. The expected week of childbirth starts on the Sunday of the week the baby is due, so count back 11 weeks from that Sunday.
What is the qualifying week for maternity pay?
The qualifying week is the 15th week before the expected week of childbirth, running Sunday to Saturday. It is the week used to check whether an employee qualifies for Statutory Maternity Pay.
When does an employee have to tell their employer they are pregnant?
By the end of the 15th week before the expected week of childbirth. That is the Saturday at the end of the qualifying week. They should also say when they want their maternity leave to start.
Can maternity leave start automatically?
Yes. If the employee is off work for a pregnancy-related reason in the 4 weeks before the expected week of childbirth, maternity leave starts automatically the next day. If the baby is born early, leave starts the day after the birth.
How long is Statutory Maternity Pay paid for?
Up to 39 weeks: 6 weeks at 90% of average weekly earnings, then 33 weeks at the statutory weekly rate or 90% of average weekly earnings if that is lower. The statutory rate is set by the government each April.
How long can maternity leave last?
Up to 52 weeks. The first 2 weeks after the birth are compulsory leave (4 weeks for factory workers), so the employee cannot work during them.
How many keeping-in-touch days can be worked?
Up to 10 keeping-in-touch (KIT) days during maternity leave.
Does this calculator work out how much maternity pay someone gets?
No. It works out the dates only. Pay depends on each person’s average weekly earnings and on the statutory rate for the year, which changes every April. Check the current rate on GOV.UK.
Sources and scope: checked 24 September 2026
This tool works out statutory dates for employees in Great Britain from the due date. It does not decide eligibility or calculate pay. Your own policy may be more generous.
General information only, not legal advice.
Track maternity leave automatically
Leavely works out the key dates from the due date, tracks KIT days, and shows managers only their own team's records. Try it free for 14 days.