Background: Minimal clinically important differences (MCIDs) at 1 year after subpectoral biceps tenodesis are unknown for the Amer- ican Shoulder and Elbow Surgeons (ASES) scale, Subjective Shoulder Value (SSV), and visual analog scale (VAS) for pain. Our objectives were to determine MCIDs for these measures at 1 year after biceps tenodesis and to identify preoperative factors that predict attainment of MCIDs. Methods: We included 52 patients who underwent arthroscopic de ?bridement, decompression, and mini-open biceps tenodesis from 2016-2018. We analyzed age, sex, body mass index value, arm dominance, diagnosis, range of shoulder motion, and preoperative and 1-year postoperative ASES, SSV, and VAS scores. MCIDs were calculated using a distribution-based method of one-half the standard deviation. Preoperative thresholds predictive of MCIDs were calculated with univariate logistic regression. Multiple logistic regres- sion was used to determine factors that predict MCIDs. Significance was set at a 2-tailed P value of <.05. Results: MCIDs for the ASES, SSV, and VAS were 13, 12, and 1.6 points, respectively. Preoperative ASES score 59 predicted MCID on the ASES (P = .03); VAS score .01); external shoulder rotation >40 degrees predicted MCID on the SSV (P = .02); and age >41 years predicted MCID on the VAS (P = .02). Conclusion: At 1 year after de bridement, decompression, and biceps tenodesis, MCIDs were 13, 12, and 1.6 points for the ASES, SSV, and VAS, respectively. Patients most likely to attain MCIDs were those aged >41 years, those with the most preoperative pain, and those with the poorest preoperative shoulder function. Level of evidence: Basic Science Study; Validation of Outcomes Instruments (C) 2020 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.