Pregnancy Notification Calculator
Calculate when you need to tell your employer about your pregnancy and plan your maternity leave dates according to UK law.
How This Works
When you’re pregnant in the UK, there’s a legal deadline for notifying your employer. You must inform them by the end of the 15th week before your baby’s expected due date—that’s around 25 weeks into your pregnancy.
Key Point: Whilst this is the legal deadline, you might want to tell your employer earlier to access pregnancy-related protections, attend antenatal appointments, or arrange workplace adjustments.
What You Must Tell Your Employer
When notifying your workplace, you need to provide three pieces of information:
- That you’re pregnant
- Your baby’s expected week of childbirth (EWC)
- The date you want to start your maternity leave
The MATB1 Certificate
Your midwife or GP will give you a MATB1 form (maternity certificate) around 20 weeks pregnant. This confirms your due date and you’ll need to provide it to your employer when giving formal notice. Keep it safe—you might need copies if you’re claiming benefits.
Your Pregnancy Timeline at Work
Week 1-12 of Pregnancy
Early pregnancy period. You can tell your employer anytime, though many wait until after the 12-week scan. If your job involves risks (heavy lifting, chemicals, long hours standing), consider notifying earlier for a risk assessment.
Week 20 of Pregnancy
You can receive your MATB1 certificate from your midwife or doctor. This form confirms your expected due date and is needed for statutory maternity pay.
Week 25 of Pregnancy (15 weeks before due date)
Legal deadline to notify your employer. You must tell them you’re pregnant, provide your due date, and state when you want maternity leave to start. Give your MATB1 certificate too.
Week 29 of Pregnancy (11 weeks before due date)
Earliest you can start maternity leave (unless baby arrives early). Some people prefer to work closer to their due date to maximise time at home with baby afterwards.
Week 36 of Pregnancy (4 weeks before due date)
If you work in a factory or shop floor environment, you cannot work past 4 weeks before your due date for health and safety reasons.
Week 38-40 of Pregnancy (Due Date)
Baby’s expected arrival. If baby arrives before your planned leave start date, your maternity leave automatically begins the day after birth.
Frequently Asked Questions
Do I have to tell my employer in writing?
Your employer can request written notice, and it’s highly recommended to put it in writing anyway. This creates evidence of your notification and triggers your employer’s health and safety duties. Keep a copy for your records.
What happens if I tell my employer after the deadline?
If you miss the 15-week deadline, you must tell your employer as soon as reasonably possible. Whilst you won’t lose your right to maternity leave, it might affect the start date of your statutory maternity pay. Valid reasons include not knowing you were pregnant or medical circumstances.
Can I change my maternity leave start date after notifying?
Yes, you can change your mind. You need to give your employer at least 28 days’ notice before either your original start date or the new start date, whichever comes first. Put the change in writing.
Should I tell my employer before 12 weeks?
This is entirely your choice. Many prefer to wait until after the 12-week scan when pregnancy risks reduce. However, telling earlier helps if you need time off for severe morning sickness, have pregnancy complications, or your job poses risks. Your employer must keep your pregnancy confidential if you request it.
What if I’m having twins or multiples?
The notification rules are the same—you still must tell your employer by 15 weeks before your due date. However, you might want to notify earlier as multiple pregnancies often have different requirements and you may need more frequent appointments.
Do I need to tell my employer immediately if I find out I’m pregnant whilst on probation?
You have the same legal rights regardless of probation status. You don’t have to tell them immediately—you can wait until the legal deadline at 15 weeks before due date. Being pregnant cannot be a reason for dismissal during or after probation.
What’s the difference between maternity leave and maternity pay?
Maternity leave is the time off work (up to 52 weeks). Maternity pay is the money you receive. Statutory Maternity Pay (SMP) is usually paid for 39 weeks. To qualify for SMP, you need to have worked for your employer continuously for at least 26 weeks by the 15th week before your due date and earn above a certain threshold.
Can my employer tell others I’m pregnant without my permission?
No. Your employer should keep your pregnancy confidential until you’re ready to share the news more widely. You can ask them to keep it between you and HR whilst you decide when to tell your team. However, they may need to inform relevant people for health and safety risk assessments.
Notification Requirements by Employment Type
| Employment Type | Notification Deadline | Maternity Leave Entitlement | Pay Entitlement |
|---|---|---|---|
| Employee (Permanent) | 15 weeks before due date | Up to 52 weeks (26 Ordinary + 26 Additional) | SMP for 39 weeks (if eligible) |
| Fixed-term Contract | 15 weeks before due date | Up to 52 weeks (even if contract ends) | SMP for 39 weeks (if eligible) |
| Agency Worker | 15 weeks before due date | Up to 52 weeks (if 12+ weeks continuous) | SMP if meet earnings threshold |
| Zero Hours Contract | 15 weeks before due date | Up to 52 weeks | SMP if earn enough |
| Self-employed | N/A (no employer) | N/A | Maternity Allowance from Jobcentre Plus |
Common Mistakes to Avoid
Missing the MATB1 form: Don’t forget to collect your MATB1 certificate at 20 weeks. Without it, your employer cannot process your statutory maternity pay. If you lose it, you can request another from your midwife or doctor, but this might delay your payments.
Not confirming in writing: Verbal notification might seem easier, but always follow up in writing. Email is fine. This protects you if there’s any dispute later about dates or whether you notified on time.
Forgetting the 28-day rule for pay: Whilst you must notify your pregnancy by 15 weeks before due date, you need to give 28 days’ notice before you want statutory maternity pay to start. These are two separate deadlines, so plan accordingly.
Not checking your contract: Your employment contract might offer enhanced maternity benefits beyond statutory minimums. Some employers require earlier notification for enhanced pay—check your contract or staff handbook.
Planning Your Announcement
Choosing when to tell your employer is personal. Here’s what to consider:
Reasons to Tell Earlier (Before 12 Weeks)
- Your job involves physical risks or hazardous substances
- You’re experiencing severe morning sickness affecting attendance
- You need time off for additional medical appointments
- You work long hours or night shifts that are becoming difficult
- You want to request flexible working arrangements early
Reasons to Wait Until After 12-Week Scan
- Reduced risk of miscarriage after first trimester
- Confirmation of pregnancy viability from scan
- More time to process the news yourself
- Avoiding premature workplace gossip
- Job doesn’t involve pregnancy-related risks
Remember: Whatever you choose, you’re protected against pregnancy discrimination from the moment you conceive, but only if your employer knows about your pregnancy. This protection includes dismissal, redundancy selection, denial of promotion, or unfavourable treatment.
What Happens After Notification
Once you’ve told your employer you’re pregnant, they have certain obligations:
Within 28 Days
Your employer must write back confirming the date your maternity leave will end (assuming you take the full 52 weeks). Keep this letter—it’s important for planning your return.
Risk Assessment
Your employer must carry out a pregnancy risk assessment for your role. This reviews whether your work involves any risks to you or your baby, such as:
- Heavy lifting or standing for long periods
- Exposure to chemicals or infectious diseases
- Working with machinery or at heights
- Night shifts or very long hours
- High stress or physically demanding tasks
If risks are identified, your employer must remove them, adjust your working conditions, or offer suitable alternative work. If no reasonable alternatives exist, they may suspend you on full pay.
Antenatal Appointments
You’re entitled to paid time off for all antenatal appointments, including NCT classes, midwife visits, scans, and antenatal clinics. You don’t need to make up the time or take it as annual leave.
References
Acas (Advisory, Conciliation and Arbitration Service). (2025). Telling your employer you’re pregnant. Retrieved from https://www.acas.org.uk/your-maternity-leave-pay-and-other-rights/telling-your-employer-youre-pregnant
GOV.UK. (2014). Pregnant employees’ rights. Retrieved from https://www.gov.uk/working-when-pregnant-your-rights
GOV.UK. (2015). Statutory Maternity Pay and Leave: employer guide. Retrieved from https://www.gov.uk/employers-maternity-pay-leave
Working Families. (2025). Maternity Leave for Employees. Retrieved from https://workingfamilies.org.uk/articles/maternity-leave-for-employees/
Working Families. (2024). How to give notice for maternity leave and pay. Retrieved from https://workingfamilies.org.uk/articles/notice-for-maternity-leave/
UNISON. (2017). Pregnancy: Your rights at work. Retrieved from https://www.unison.org.uk