BackgroundThe UK was the first country to launch a national pandemic COVID-19 vaccination programme, which was implemented swiftly despite significant vaccine supply constraints. The delivery strategy used a combination of mass vaccination sites operated by NHS secondary care providers and local sites led by Primary Care Networks, and local pharmacies. Despite nation-wide rollout, persistent gaps in coverage continued to affect particular populations, including ethnic minority and marginalised social groups.AimThe study examined sub-national immunisation commissioners and providers’ perspectives on how the COVID-19 vaccine programme was operationalised, and how delivery strategies impacted inequalities in access to vaccination services and uptake. The study aimed to inform national programme implementation, sustainability and future pandemic preparedness.MethodsQualitative research was conducted in eight local NHS areas in 4 regions of England. Semi-structured interviews were performed with 82 sub-national NHS and public health vaccine providers and commissioners.ResultsEngland’s COVID-19 vaccination programme was described as top down, centralised and highly political. The programme gradually morphed from a predominantly mass vaccination strategy into more locally driven and tailored approaches able to respond more effectively to inequalities in uptake. Over time more flexibility was introduced, as providers adapted services by “working around” the national systems for vaccine supply and appointment booking. The constant change faced by providers and commissioners was mitigated by high staff motivation and resilience, local collaboration and pragmatism. Opportunities for efficient implementation were missed because priority was given to achieving national performance targets at the expense of a more flexible sub-national tailored delivery.ConclusionPandemic vaccination delivery models need to be adapted for underserved and hesitant groups, working in collaboration with local actors. Learnings from the initial COVID-19 vaccine roll-out in England and elsewhere is important to inform future pandemic responses, in tailoring strategies to local communities, and improve large-scale vaccination programmes.