Purpose To evaluate the uptake and effect of RENEW, a 12-week exercise referral programme for young adult cancer survivors delivered by Trekstock, a UK-based cancer charity. Methods The RENEW programme provides one-to-one individually tailored support from a level-4 cancer-rehabilitationqualified gym instructor, free gym membership and access to information resources online. Objective and self-report data on cardiorespiratory function, strength, body composition, fatigue, sleep quality and general health-related quality of life (HRQoL) was collected from participants before the programme (week 0), immediately after (week 12) and 1 month later (week 16). Results Forty-eight young adults (83% female; mean age, 29 years) with a history of cancer took part within the 12-week programme and completed the evaluation measures. Physical activity (PA) levels significantly increased following the programme and remained raised at follow-up. Improvements in physical function were significant: peak expiratory flow (mean change, 30.96, p = 0.003), sit-and-reach test (mean change, 6.55 ± 4.54, p < 0.0001), and 6-mine-walk test (mean change, 0.12 ± 0.04, p < 0.0001). No significant changes in BMI, weight or muscle mass were observed. Improvements in fatigue, sleep and HRQoL were observed across the programme and at follow-up (mean change, weeks 0-16; 8.04 ± 1.49 p < 0.01; 1.05 ± 0.49 p < 0.05; and − 0.9 ± 0.46 p = 0.051, respectively). Changes in self-efficacy to exercise and motivations to exercise were not observed at 12 weeks or at follow-up. Conclusions Results suggest that the RENEW exercise referral programme has a positive impact upon some domains of physical function and well-being among young adult cancer survivors. Implication for cancer survivors Exercise referral programmes delivered by charity organisations are one means by which PA behaviour change support may be widely disseminated to young adult cancer survivors. Health professionals and charitable bodies specialising in the care of young adults with cancer should look to address factors which prevent engagement and uptake of 'real-world' PA interventions such as the RENEW programme.