SPM20505 - Statutory Maternity Pay (SMP) – Medical evidence

What is acceptable evidence of pregnancy

The employee must produce medical evidence of the date the baby is due. This will normally be on a Maternity Certificate MAT B1, which shows the date the baby is due, see SPM20325.

The MAT B1 is given to the employee by the doctor or midwife. The date given on the MAT B1 can not be changed. Only in exceptional cases, a doctor or midwife who has given a fresh examination would issue a new MATB1.

In cases where a MATB1 is lost or mislaid a replacement can be issued and clearly marked “duplicate”.

It cannot be issued before the start of the 20th week before the EWC (before September 2001, this was the 14th week). The date of issue is the date it was signed by the doctor or midwife.

The employer may be able to calculate what SMP is due before they receive medical evidence but they must not pay SMP until acceptable medical evidence is received. Although a birth certificate is acceptable as proof that a baby has been born, the employer still needs evidence of the date the baby was due, in order to check that the employee satisfies the continuous employment rule and to calculate the AWE.