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Statutory Maternity Pay (SMP)
You can get Statutory Maternity Pay (SMP) for up to 39 weeks, as long as you meet the conditions.

To qualify for Statutory Maternity Pay you must have been:

employed by the same employer continuously (some breaks do not interrupt continuous employment) for at least 26 weeks into the 15th week before the week your baby is due; and
earning an average of at least £90 a week (before tax)
To claim Statutory Maternity Pay you must tell your employer at least 28 days before the date you want to start your Statutory Maternity Pay. Your employer may need you to tell them in writing.

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How much SMP you'll get
If you get SMP, your employer will pay you 90 per cent of your average weekly earnings for the first six weeks, then up to £117.18 for the remaining 33 weeks. You pay tax and National Insurance in the same way as on your regular wages. Your employer reclaims the majority of SMP from their National Insurance contributions and other payments. To qualify for SMP you must pay tax and national insurance as an employee (or would pay if you earned enough or are old enough).

If you’re an agency worker, you have the right to Maternity or Paternity Pay, but not Maternity or Paternity Leave. You can get Statutory Sick Pay if you’ve worked for the same agency for more than three months. HM Revenue and Customs (HMRC) can help decide what you are entitled to.