Calculate UK Maternity Leave and Pay

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How We Calculate Maternity Leave and SMP Dates

Start with the due date

We use the due date to work out the expected week of childbirth and all key deadlines.

Find the qualifying week

We count back 15 weeks to calculate the qualifying week, join date, and notice deadline.

Work out the pay period

We show the standard 8-week period used to assess average weekly earnings for SMP.

Show leave start dates

We calculate the earliest leave start date and the sickness trigger date near the due week.

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Enter the expected week of childbirth due date and we’ll calculate key SMP/maternity dates.
Join date to qualify for SMP
Latest start date to meet the 26-week service requirement.
Maternity pay calculation period
Standard 8-week period ending with the qualifying week.
Notification deadline
Employee must notify by the end of the qualifying week.
Earliest commencement date
The earliest date maternity leave can begin.
Start date if employee is marked sick
Automatically triggered if sick from the 4th week before EWC.

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Maternity leave calculator

Understand maternity leave, pay, and key deadlines

Our maternity leave calculator helps employers and employees understand key maternity deadlines, leave dates, and Statutory Maternity Pay eligibility in one place.

Enter the expected date of birth to quickly identify important dates, including the latest date an employee must have joined the business to qualify for SMP, the 8-week pay calculation period, and the earliest date maternity leave can start.

With everything clearly laid out, it becomes much easier to plan ahead, stay compliant, and support pregnant employees and new mothers with confidence.

Maternity leave and maternity pay are different

Maternity leave is the time an employee takes off work before and after the birth of their baby. Maternity pay is the pay they receive while on that leave.

These are separate statutory entitlements with different eligibility rules, and some employers may choose to offer enhanced contractual maternity pay on top of the statutory minimum.

How long maternity leave lasts

Eligible employees can take up to 52 weeks of maternity leave in total, made up of 26 weeks of Ordinary Maternity Leave and 26 weeks of Additional Maternity Leave.

Maternity leave can start up to 11 weeks before the expected week of childbirth, and employees must take at least 2 weeks’ compulsory leave after birth, or 4 weeks if they work in a factory.

What the calculator helps you check

The calculator helps you identify the key dates and conditions that affect leave and pay entitlement.

Due date → notice deadlines → qualifying week → pay period → leave start date

It also helps show how sickness within four weeks of the due date may affect maternity leave planning.

What should employers know?

Employers have a legal duty of care to pregnant employees and new mothers, from workplace risk assessments through to leave, pay, record keeping, and ongoing employment protections.

Notice and proof

Employees must tell their employer the baby’s due date and when they want maternity leave to start at least 15 weeks before the baby is due, and must usually give 28 days’ notice for SMP.

SMP eligibility

To qualify for Statutory Maternity Pay, employees must meet payroll, service, notice, proof of pregnancy, and average earnings requirements in the qualifying week and relevant pay period.

Protected rights

Employees on maternity leave continue to have employment protections, including holiday accrual, pay rises, the right to return to work, and strengthened redundancy protection.

Who qualifies for maternity leave and SMP?

Employees are entitled to Statutory Maternity Leave if they have an employment contract and give the correct notice, regardless of how long they have worked for the business.

Statutory Maternity Pay has different rules. Employees must be on the payroll in the qualifying week, have at least 26 weeks’ continuous service up to that point, provide the correct notice and proof of pregnancy, and earn at least the minimum weekly amount during the relevant 8-week period.

Employer responsibilities and support

Employers must carry out maternity risk assessments, make reasonable workplace adjustments where needed, pay SMP accurately where eligible, and avoid discrimination connected to pregnancy or maternity leave.

They also need to support accurate record keeping and understand related family leave options such as paternity leave, Shared Parental Leave, Unpaid Parental Leave, and Neonatal Care Leave and Pay.

Plan maternity leave with clarity

Use the calculator to understand key maternity deadlines, check SMP eligibility, and prepare for leave with confidence.

Use the maternity calculator
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