As well as SARS-CoV2, other common winter respiratory viruses place pressure on the NHS, including influenza. The circulation of influenza was very limited in the UK in the 2020 to 2021 season due to the use of non-pharmaceutical interventions, including social distancing measures. As a result, a lower level of population immunity against influenza is expected. Mathematical modelling indicates the 2021 to 2022 influenza season in the UK could be up to 50% larger than typically seen [footnote 5]. It is also possible that the 2021 to 2022 influenza season will begin earlier than usual. To mitigate the potential impact from influenza, JCVI has advised extension of the influenza vaccination programme to adults aged 50 years and over in winter 2021 to 2022. It is paramount that as many eligible adults as possible take up the offer of influenza vaccination, with those at highest risk vaccinated as early as possible. JCVI considers that a synergistic approach to the delivery of COVID-19 and influenza vaccination may support delivery and maximise uptake of both vaccines in the population. The priority for deployment teams should be the delivery of influenza and COVID-19 booster vaccines to individuals identified in stage 1 at the earliest possible time, progressing to COVID-19 booster revaccination of individuals identified in stage 2 without causing undue delay and without displacement of the timely delivery of annual influenza vaccinations. Within each of the stages, where practicable, those with the longest interval since the second dose of their primary course of vaccination should be called first. Early evidence on the concomitant administration of COVID-19 and influenza vaccines used in the UK supports the delivery of both vaccines at the same time where appropriate [footnote 6].