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.
If you’re off work sick for more than 7 days, your employer will usually ask for a fit note (or Statement of Fitness for Work) from a GP or hospital doctor.
Fit notes are sometimes referred to as medical statements or a doctor’s note.
For further information on sick/fit notes click here.
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).