Aims: The aim was to analyze the ability to return to work (RTW) after implantation of reverse total shoulder arthroplasty (RTSA) with special attention to heavy labourers. Methods: All working patients younger than 60 years of age who underwent RTSA between September 2005 and October 2021 were retrospectively evaluated for their ability to RTW. Basic demographic information, job intensity, change of work, and preoperative sick leave were collected. Constant-Murley score (CS) and Subjective Shoulder Value (SSV) preoperatively and at two years' follow-up, complications, and revision surgeries were used to evaluate the outcome. Logistic regression analysis was used to predict RTW. Results: A total of 167 of 209 eligible patients were employed at the time of surgery (median age 55 years (IQR 50.3 to 57.8), 34.1% (n = 57) female), of whom 75 (44.9%), 61 (36.5%), and 31 (18.6%) were classified to have light, medium, or heavy work intensity, respectively. Postoperatively, 73.7% (123/167) of them RTW at a median time of four months (IQR 2 to 7). Of those who RTW, 9.8% of patients (12/123) had to change occupation to less demanding jobs. Patients with high-intensity jobs had a lower RTW rate (19/31; 61.3%) compared with those with light (59/75; 78.7%) and medium-intensity jobs (45/61; 73.8%). Patients who RTW had better pre- and postoperative outcomes as well as greater improvement in relative CS (76% vs 34%; p < 0.001), CS for pain (14 vs 7 with 15 as best value; p < 0.001), and SSV (75% vs 20%; p < 0.001). Logistic regression analysis showed that absence of preoperative sick leave (OR 6.81 (95% CI 2.63 to 19.4); p < 0.001) was associated with higher RTW rates. Conclusion: More than two-thirds of preoperatively working patients were able to RTW after RTSA, depending on work intensity. Higher RTW rates were seen in patients who were not on sick leave preoperatively. This information is highly relevant for the surgeon to counsel patients accordingly and possibly limit expectations, especially in heavy workers.