OBJECTIVE: To explore public attitudes to COVID-19 vaccines in the UK, focused on intentions and decisions around taking vaccines, views on ‘vaccine passports’, and experiences and perspectives on post-vaccination behaviour.DESIGN: Qualitative study consisting of 6 online focus groups conducted between 15th March – 22nd April 2021. SETTING: Online video conferencingPARTICIPANTS: 29 adult UK-based participantsRESULTS: Three main groups regarding participants’ decision or intention to receive a COVID-19 vaccine were identified: (1) Accepters, (2) Delayers and (3) Refusers. Two reasons for vaccine delay were identified: delay due to a perceived need more information and delay until vaccine was “required” in the future. Three main facilitators (Vaccination as a social norm; Vaccination as a necessity; Trust in science) and six barriers (Preference for “natural immunity”; Concerns over possible side effects; Distrust in government; Perceived lack of information; Conspiracy theories; “Covid echo chambers”) to vaccine uptake were identified. For some delayers, 'vaccine passports' were perceived to be a reason why they would get vaccinated in the future. However, vaccine passports were controversial, and were framed in four main ways: as “a necessary evil”; as “Orwellian”; as a “human rights problem”; and as a source of confidence”. Participants generally felt that receiving a vaccine was not changing the extent to which people were adhering to COVID-19 measures. CONCLUSIONS: Overall positive sentiment around vaccines is high. However, there remains a number of potential barriers which might be leading to vaccine delay in some. ‘Vaccine delay’ might be a more useful and precise construct than vaccine hesitancy in explaining why some may initially ignore or be uncertain about vaccination invitations. Vaccine passports may increase or ‘nudge’ uptake in some delayers but may be unpopular in others. Earlier concerns that vaccination might reduce adherence to social distancing measures are not borne out in our data, with most people reporting adherence and caution.