If you are sick for less than 7 continuous days, then the NHS does not provide sick notes. The government requires that patients self-certify if they are off sick for 7 days or less.
Patients who take sick leave for less than 7 continuous days should complete a Self Certification (SC2) form which is available from their employer or on the HMRC website.
The NHS provides sickness certification only after 7 continuous days of illness. If patients are sick for more than 7 days, an NHS certificate may be issued but patients will need to contact the surgery as it may be necessary to discuss their health with the GP. Please visit the Direct Gov website for full information. Please note, sick notes are at the discretion of your GP.
HMRC state that patients do not require a GP note to declare that they can go back to work.