Been off Work
Illness lasting fewer than 7 calendar days
You do not require a doctor's sickness certificate for any illness lasting seven calendar days or less. Your employer may however require you to complete a self-certification form (SC2) which is available from your employer or on the HMRC website.
You do not need to provide a medical certificate from a doctor for sick leave of 7 calendar days or fewer. If your employer insists on medical certification for this period, you will be asked to pay a private fee for such a certificate, as this certification is not part of the NHS service. Please refer to our section on Non-NHS services for further details.
Ilness lasting longer than 7 calendar days
If you are sick for more than seven days, your employer can ask you to give them some form of medical evidence to support payment of SSP (statutory sick pay).
It is up to your employer to decide whether you are incapable of work. A medical certificate, now called a 'Statement of Fitness for Work’ (see below) from your doctor is strong evidence that you are sick and would normally be accepted, unless there is evidence to prove otherwise.
You could also provide evidence from someone who is not a medical practitioner, e.g. a dentist. Your employer will decide whether or not this evidence is acceptable. If your employer has any doubts, they may still ask for a medical certificate from your GP.