You do not require a doctor's sickness certificate for any illness lasting seven 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 .
Evidence that you are sick
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.
Statement of Fitness for Work - ’Fit Note'
The 'fit note' was introduced on 6 April 2010. With your employer's support, the note will help you return to work sooner by providing more information about the effects of your illness or injury.
For more information see the DirectGov website (where this information was sourced)
'FIT' notes if you have sustained a fracture, had an operation or treatment in hospital
If you have been in hospital because you have sustained a fracture, recently had surgery or hospital treatment, it is the hospital’s responsibility to issue you with a “fit certificate”. We are unable to issue certificates in these circumstances.
If you are due to be admitted to hospital for surgery or treatment, we would ask you to think ahead if you will require a “Fit Certificate” for any purpose, and request one at the time of discharge.
Sickness certificates for academic examination purposes
OFQUAL (the agency that controls the examination boards) has confirmed that there is NO requirement for students to obtain a medical certificate in support of an application for special consideration.
Students are asked for information in support of their application, but this may take the form of a statement by the school or centre.
If your school or centre insists on having a medical certificate, please let us know so that we can send them details of the OFQUAL decision.