A flu jab is a seasonal vaccination designed to help protect against influenza viruses expected to circulate during the flu season.
The NHS offers flu vaccination to people who are considered more likely to develop serious complications from flu. This includes groups such as older adults, pregnant women, eligible children and people with certain health conditions.
Flu vaccination is offered each year because the viruses that circulate can change over time, and seasonal vaccination programmes are updated accordingly.
For the 2026 to 2027 programme in England, vaccination begins at different times depending on the eligible group. The main adult programme starts from 1 October 2026, while vaccination for pregnant women and eligible children begins from 1 September 2026.
A flu jab does not protect against every respiratory infection, so people can still catch other illnesses such as the common cold.
If you are unsure whether you are eligible, check the latest NHS guidance or speak with a pharmacist or GP.