Objectives: The study objectives were to describe the compounded complication rate of minimally invasive repair of pectus excavatum, identify predisposing risk factors, and evaluate the optimal timing of correction. Minimally invasive repair of pectus excavatum is the standard treatment for pectus excavatum and consists of 2 invasive procedures, for example, correction with bar insertion followed by bar removal after 2 to 3 years. Methods: A retrospective cohort study identifying children, adolescents, and adults of both genders corrected for pectus excavatum with minimally invasive repair of pectus excavatum between 2001 and 2022. Information on complications related to bar insertion and removal procedures for each individual patient was compiled into a compounded complication rate. Complication severities were categorized according to the Clavien-Dindo classification. Results: A total of 2013 patients were corrected by minimally invasive repair of pectus excavatum with a median age (interquartile range) for correction of 16.6 (5) years. Overall compounded complication rate occurred at a frequency of 16.4%, of which 9.3% required invasive reinterventions (Clavien-Dindo classification ≥IIIa). The complication rate related to bar insertion was 2.6-fold higher compared with bar removal (11.8% vs 4.5%, respectively). Multivariable analysis revealed age (adjusted odds ratio, 1.05; P < .001), precorrection Haller Index (adjusted odds ratio, 1.10; P < .033), and early-phase institutional experience (adjusted odds ratio, 1.59; P < .002) as independent predisposing risk factors. The optimal age of correction was 12 years, and the compounded complication rate correlated exponentially with age with a doubling time of 7.2 years. Complications increased 2.2-fold when the Haller index increased to 5 or more units. Conclusions: Minimally invasive repair of pectus excavatum is associated with a high compounded complication rate that increases exponentially with age and high Haller Index. Consequently, we recommend repair during late childhood and early adolescence, and emphasize the importance of informing patients and relatives about the significant risks of adult correction as well as the need of 2 consecutive procedures taking the complication profile into account before planning surgery.