Objectives: To examine if exercise referral schemes (ERS)s are associated with meaningful changes in health and wellbeing in a large cohort of individuals throughout England, Scotland, and Wales from The National Referral Database. Methods: Data were obtained from 23,731 participants from 13 different ERSs lasting 6 weeks to 3 months. Changes from pre- to post-ERS in health and wellbeing outcomes were examined including body mass index (BMI), blood pressure (SBP & DBP), resting heart rate (RHR), short Warwick Edinburgh Mental Wellbeing Scale (SWEMWBS), World Health Organization Well-Being Index (WHO-5), Exercise Related Quality of Life scale (ERQoL), and Exercise Self-Efficacy Scale (ESES). Two-stage individual patient data meta-analysis was used to generate effect estimates. Results: Estimates [95%CIs] revealed statistically significant changes occurred compared to point nulls for BMI (-0.55 kg.m2 [-0.69 to -0.41]), SBP (-2.95 mmHg [-3.97 to -1.92]), SWEMWBS (2.99 pts [1.61 to 4.36]), WHO-5 (8.78 pts [6.84 to 10.63]), ERQoL (15.26 pts [4.71 to 25.82]), ESES (2.58 pts [1.76 to 3.40]), but not RHR (0.22 fc [-1.57 to 1.12]), DBP (-0.93 mmHg [-1.51 to -0.35]). However, comparisons of estimates [95%CIs] against null intervals suggested the majority of outcomes may not improve meaningfully. Conclusions: We considered whether meaningful health and wellbeing changes occur in people who are undergoing ERSs? Regarding this broad question, these results demonstrate that, although many health and wellbeing outcomes improved, the changes be not achieve meaningful levels. This suggests the need to consider the implementation of ERSs more critically to discern how to maximize their effectiveness.