Background: Real world data supporting the effectiveness of the COVID-19 vaccination strategy in the UK population is needed to guide health policy. This real-word data-driven evidence study of the UK COVID-19 Vaccination Programme in the Northwest London (NWL) population used a unique dataset established as part of the Gold Command Covid-19 response in NWL (iCARE https://imperialbrc.nihr.ac.uk/facilities/icare/), which included the pre-established Whole System Integrated Care (WSIC) data collated for the purposes of population health in the sector. Objective: To assess the early vaccine administration coverage and vaccine effectiveness and outcome data across an integrated care system of eight CCGs leveraging a unique population-level care dataset Methods: Design - Retrospective cohort study. Setting - Individuals eligible for COVID 19 vaccination in North West London based on linked primary and secondary care data. Participants - 2,183,939 individuals eligible for COVID 19 vaccination Results: During the NWL vaccine programme study time period 5.88% of individuals declined and did not receive a vaccination. Black or black British individuals had the highest rate of declining a vaccine at 16.14% (4,337). There was a strong negative association between deprivation and rate of declining vaccination (r=-0.94, p