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Maternity leave calculator

Work out the key maternity leave dates from the due date, then check Statutory Maternity Pay eligibility and the weekly amounts.

  • Free to use
  • No signup
  • 2026/27 SMP rates
Use the calculator

Work out the maternity dates

Enter the due date and planned start. Add the employment start date and average weekly earnings to check Statutory Maternity Pay.

From the MATB1 certificate or the midwife's letter.

Statutory Maternity Pay (optional)

Usually the average over the 8 weeks up to the last normal payday on or before the Saturday of the qualifying week.

Returning early (optional)

Leave blank for the full 52 weeks, which needs no notice to return.

Sunday 27 June 2027first day back after the full 52 weeks of leave from Sunday 28 June 2026

Key dates

  1. Sunday 5 April 2026 to Saturday 11 April 2026SMP qualifying weekThe 15th week before the due week, used for the SMP service and earnings tests.
  2. Saturday 11 April 2026Notice dueThe employee tells the employer about the pregnancy, the due week and the planned start. The employer then has 28 days to confirm the end date in writing.
  3. Sunday 3 May 2026Earliest planned startThe beginning of the 11th week before the due week.
  4. Sunday 31 May 2026SMP notice dueAt least 28 days before SMP starts. Proof of pregnancy, such as a MATB1, is due within 21 days of the SMP start date.
  5. Sunday 21 June 2026Automatic start window opensFrom this day, a pregnancy-related absence starts maternity leave automatically the next day.
  6. Sunday 28 June 2026Leave startsOrdinary Maternity Leave, the first 26 weeks. SMP usually starts the same day.
  7. Sunday 19 July 2026 to Saturday 25 July 2026Expected week of childbirthThe Sunday-to-Saturday week that contains the due date.
  8. Wednesday 22 July 2026 to Tuesday 4 August 2026Compulsory leave (2 weeks)Counted from the birth. These dates assume the baby arrives on the due date.
  9. Sunday 27 December 2026Additional Maternity Leave startsThe second 26 weeks.
  10. Saturday 26 June 2027Last day of leaveThe end of the full 52 weeks.
  11. Sunday 27 June 2027First day backAfter the full 52 weeks. Returning on this date needs no further notice.

Statutory Maternity Pay

26 weeks' employment
Met
Earnings at least £129 a week
Met
Weeks 1 to 6
£540 a week
Weeks 7 to 39
£194.32 a week
Total over 39 weeks
£9,652.56

Paid from Sunday 28 June 2026 to Saturday 27 March 2027, before tax and National Insurance.

The working

  1. Due date Wednesday 22 July 2026: the expected week of childbirth runs Sunday 19 July 2026 to Saturday 25 July 2026
  2. 15th week before it: 5 April 2026 to 11 April 2026. Notice of the pregnancy, due week and planned start is due by Saturday 11 April 2026
  3. 11th week before it begins Sunday 3 May 2026: the earliest planned start
  4. 4th week before it begins Sunday 21 June 2026: a pregnancy-related absence from then starts leave automatically the next day
  5. Leave starts Sunday 28 June 2026. Ordinary Maternity Leave: 26 weeks to Saturday 26 December 2026
  6. Additional Maternity Leave: 26 weeks from Sunday 27 December 2026 to Saturday 26 June 2027
  7. After the full 52 weeks, the first day back is Sunday 27 June 2027
  8. Compulsory leave: 2 weeks from the birth. If the baby arrives on the due date, that is 22 July 2026 to 4 August 2026
  9. SMP service test: started on or before Saturday 18 October 2025 for 26 weeks' continuous employment into the 15th week before the due week. Started Monday 4 September 2023: met
  10. SMP earnings test: £600 a week against the £129 Lower Earnings Limit: met
  11. Weeks 1 to 6 (28 June 2026 to 8 August 2026): 90% of £600 = £540 a week, rounded up to the penny
  12. Weeks 7 to 39 (9 August 2026 to 27 March 2027): the lower of £194.32 and £540 = £194.32 a week
  13. SMP total = 6 × £540 + 33 × £194.32 = £9,652.56

Worth knowing

  • If the baby is born before the planned start, leave starts the day after the birth and every later date moves with it.
  • The employee can change the planned start by giving 28 days' notice, or as soon as reasonably practicable. Update the written confirmation and payroll together.
  • The planned start falls in the 4 weeks before the due week. A pregnancy-related absence from Sunday 21 June 2026 would start leave earlier, on the day after the first day off.
  • The service test also needs the employee to still be employed in the qualifying week. Breaks, a change of employer or a TUPE transfer can affect continuity.
  • Average weekly earnings come from gross pay in the relevant period: usually the 8 weeks up to the last normal payday on or before the Saturday of the qualifying week. Back pay, a pay rise or a birth before or during that week change the calculation.
  • These are the Great Britain rules. Northern Ireland has its own legislation, so check nidirect for an employee there.

Basis: Great Britain maternity leave and Statutory Maternity Pay rules as published on GOV.UK: notice by the end of the 15th week before the expected week of childbirth, leave from the 11th week before it at the earliest, 52 weeks of leave and SMP at the 2026/27 rates. Rules checked 8 November 2026. Each weekly SMP payment is rounded up to the next penny, as GOV.UK's own calculator does. Check the facts and jurisdiction before relying on the dates. Rules checked .

GOV.UK maternity leaveGOV.UK SMP eligibilityGOV.UK employer guideGOV.UK 2026/27 ratesMaternity Regulations 1999, regulation 6
The method

How the maternity dates are worked out

Every date counts from the expected week of childbirth: the Sunday-to-Saturday week that contains the due date.
  1. 1

    Find the expected week

    The week starts on the Sunday on or before the due date. Notice is due by the Saturday that ends the 15th week before it, and the earliest planned start is the Sunday that begins the 11th week before it.

  2. 2

    Count 52 weeks from the start

    Ordinary Maternity Leave covers the first 26 weeks and Additional Maternity Leave the next 26. Compulsory leave covers the 2 weeks from the birth, or 4 for factory work.

  3. 3

    Check pay in the qualifying week

    SMP needs 26 weeks' continuous employment into the 15th week before the expected week and average weekly earnings of at least £129. It pays 90% for 6 weeks, then the lower of £194.32 and 90% for 33 weeks.

Worked example

Worked example: leave three weeks before the due week

The baby is due on Wednesday 22 July 2026. The employee started work on 4 September 2023, earns £600 a week on average and plans to start leave on Sunday 28 June 2026.

Inputs

  • Due date: 22 July 2026
  • Planned start: 28 June 2026
  • Employment start: 4 September 2023
  • £600 average weekly earnings

Working

  1. Due date Wednesday 22 July 2026: the expected week of childbirth runs Sunday 19 July 2026 to Saturday 25 July 2026
  2. 15th week before it: 5 April 2026 to 11 April 2026. Notice of the pregnancy, due week and planned start is due by Saturday 11 April 2026
  3. 11th week before it begins Sunday 3 May 2026: the earliest planned start
  4. 4th week before it begins Sunday 21 June 2026: a pregnancy-related absence from then starts leave automatically the next day
  5. Leave starts Sunday 28 June 2026. Ordinary Maternity Leave: 26 weeks to Saturday 26 December 2026
  6. Additional Maternity Leave: 26 weeks from Sunday 27 December 2026 to Saturday 26 June 2027
  7. After the full 52 weeks, the first day back is Sunday 27 June 2027
  8. Compulsory leave: 2 weeks from the birth. If the baby arrives on the due date, that is 22 July 2026 to 4 August 2026
  9. SMP service test: started on or before Saturday 18 October 2025 for 26 weeks' continuous employment into the 15th week before the due week. Started Monday 4 September 2023: met
  10. SMP earnings test: £600 a week against the £129 Lower Earnings Limit: met
  11. Weeks 1 to 6 (28 June 2026 to 8 August 2026): 90% of £600 = £540 a week, rounded up to the penny
  12. Weeks 7 to 39 (9 August 2026 to 27 March 2027): the lower of £194.32 and £540 = £194.32 a week
  13. SMP total = 6 × £540 + 33 × £194.32 = £9,652.56

Leave runs from 28 June 2026 to 26 June 2027, with notice due by 11 April 2026. SMP is £540 a week for 6 weeks, then £194.32 for 33 weeks: £9,652.56 in total.

Use it with context

The dates are the start of the plan

Use the dates to confirm leave in writing and brief payroll. Early births, changed plans and pay questions still need the facts of the case.

This calculator covers

  • The expected week, notice deadline and earliest start
  • Ordinary and Additional Maternity Leave end dates
  • Compulsory leave, including the 4-week factory rule
  • SMP service and earnings tests at 2026/27 rates
  • 8 weeks' notice for an early return

Check the full guidance for

  • A birth before or during the qualifying week
  • Pay rises, back pay and irregular earnings in the relevant period
  • Stillbirth, premature birth and Neonatal Care Leave
  • Keeping in touch days, holiday and Shared Parental Leave
  • Northern Ireland, which has its own legislation
From calculation to record

Keep the dates with the person

HollyHR keeps time off and documents on each person record, so the agreed leave dates and the MATB1 sit together.

See time off in HollyHR
Questions

About the maternity leave calculator

When must an employee tell the employer about maternity leave?

By the end of the 15th week before the expected week of childbirth, or as soon as reasonably practicable if that is not possible. They give the due week and the date they want leave to start. The employer then confirms the end date in writing within 28 days.

What is the earliest maternity leave can start?

The beginning of the 11th week before the expected week of childbirth. Leave starts earlier only if the baby is born first, when it starts the day after the birth.

When does maternity leave start automatically?

If the employee is off work for a pregnancy-related reason on or after the start of the 4th week before the expected week, leave starts the day after the first day of absence. It also starts the day after an early birth.

Who qualifies for Statutory Maternity Pay?

An employee who has worked for the employer continuously for at least 26 weeks into the qualifying week, the 15th week before the expected week, and whose average weekly earnings are at least £129. They also give 28 days' notice and proof of pregnancy, such as a MATB1.

How much is Statutory Maternity Pay in 2026/27?

90% of average weekly earnings for the first 6 weeks, then £194.32 or 90% of average weekly earnings, whichever is lower, for the next 33 weeks. The rate applies from 5 April 2026 and normally changes each April.

How much notice does an employee need to return early?

At least 8 weeks' notice of the new return date. Without it, the employer can postpone the return until 8 weeks have passed, but not beyond the end of the leave. Returning after the full 52 weeks needs no notice.

Does the calculator work for Northern Ireland?

It uses the Great Britain rules. Northern Ireland has its own legislation and guidance, so check nidirect for an employee there before relying on the dates.

Keep going

Useful next steps

GuideMaternity and family leave
GlossaryMaternity leave
GlossaryStatutory Maternity Pay

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