BACKGROUND: Free tissue transfer is often considered a last resort in burn reconstruction due to its complexity and associated risks. A comprehensive review on free flap outcomes in delayed burn reconstruction is currently lacking. The study aimed to evaluate the available evidence on the failure and contracture recurrence rates in free flap delayed burn reconstruction. METHODS: A systematic review and meta-analysis was conducted and reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The protocol was registered on PROSPERO (CRD42023404478). The following databases were accessed: Embase, PubMed, Web of Science, and Cochrane Library. The measured outcomes were free flap loss and contracture recurrence rate. RESULTS: Of the 1262 retrieved articles, 40 qualified for inclusion, reporting on 1026 free flaps performed in 928 patients. The mean age was 29.25 years [95% confidence interval (CI), 24.63-33.88]. Delayed burn reconstruction was performed at an average of 94.68 months [95% CI, - 9.34 to 198.70] after initial injury, with a follow-up period of 23.02 months [95% CI, 4.46-41.58]. Total flap loss rate was 3.80% [95% CI, 2.79-5.16] and partial flap loss rate was 5.95% [95% CI, 4.65-7.57]. Interestingly, burn contracture recurrence rate was 0.62% [95% CI, 0.20-1.90]. CONCLUSIONS: This systematic review provides a comprehensive evaluation of the free flap outcomes in delayed burn reconstruction. The flap loss rate was relatively low, given the complexity of the procedure and potential risks. Furthermore, burn contracture rate was found to be extremely low. This study demonstrates that free flaps are a safe and effective option for delayed burn reconstruction.