ObjectiveThe aim of the study was to assess the clinical effectiveness of the national cardiovascular disease (CVD) prevention programme—National Health Service Health Check (NHSHC) in reduction of CVD risk.DesignProspective cohort study.Setting147 primary care practices in Leicestershire and Northamptonshire in England, UK.Participants27 888 individuals undergoing NHSHC with a minimum of 18 months of follow-up data.Outcome measuresThe primary outcomes were NHSHC attributed detection of CVD risk factors, prescription of medications, changes in values of individual risk factors and frequency of follow-up.ResultsAt recruitment, 18% of participants had high CVD risk (10%–20% 10-year risk) and 4% very high CVD risk (>20% 10-year risk). New diagnoses or hypertension (HTN) was made in 2.3% participants, hypercholesterolaemia in 0.25% and diabetes mellitus in 0.9%. New prescription of stains and antihypertensive medications was observed in 5.4% and 5.4% of participants, respectively. Total cholesterol was decreased on average by 0.38 mmol/L (95% CI −0.34 to −0.41) and 1.71 mmol/L (−1.48 to −1.94) in patients with initial cholesterol >5 mmol/L and >7.5 mmol/L, respectively. Systolic blood pressure was decreased on average by 2.9 mm Hg (−2.3 to −3.7), 15.7 mm Hg (−14.1 to −17.5) and 33.4 mm Hg (−29.4 to −37.7), in patients with grade 1, 2 and 3 HTN, respectively. About one out of three patients with increased CVD risk had no record of follow-up or treatment.ConclusionsMajority of patients identified with increased CVD risk through the NHSHC were followed up and received effective clinical interventions. However, one-third of high CVD risk patients had no follow-up and therefore did not receive any treatment. Our study highlights areas of focus which could improve the effectiveness of the programme.Trial registration numberNCT04417387.