This study assesses the relationship between the glenoid bone loss size and range of motion, functional outcomes, and complications in high-performance athletes undergoing bone block surgery for anterior shoulder instability.  This retrospective study evaluated postoperative outcomes in athletes submitted to bone block surgery for anterior shoulder instability. In 5 years, 41 shoulders underwent the procedure; 20 had bone losses up to 15%, and 21 shoulders presented bone losses ranging from 15% and 25%.  There was no statistically significant difference regarding postoperative complications, new dislocations, and the rate of return to sports. In addition, the quantitative criteria evaluated, i.e., ranges of motion and functional scores, showed no statistically significant difference between groups. The size of the bone loss per se does not seem to affect functional outcomes and complications from these procedures, which are safe techniques for small and large bone losses.