Abstract Purpose The TransREctus sheath PrePeritoneal procedure (TREPP) was introduced as an alternative open and preperitoneal technique for inguinal hernia mesh repair, demonstrating safety and efficacy in retro- and prospective studies. However, little is known about the technique’s inherent learning curve. In this study, we aimed to determine TREPP learning curve effects after its implementation in high-volume surgical practice. Methods All primary, unilateral TREPP procedures performed in the first three years after implementation (between January 2016 and December 2018) were included out of a large preconstructed regional inguinal hernia database. Data were analyzed on outcome (i.e., surgical complications, hernia recurrences, postoperative pain). Learning curve effects were analyzed by assessing outcome in relation to surgeon experience. Results In total, 422 primary, unilateral TREPP procedures were performed in 419 patients. In three patients a unilateral TREPP procedure was performed on both sides separated in time. A total of 99 surgical complications were registered in 83 procedures (19.6% of all procedures), most commonly inguinal postoperative pain (8%) and bleeding complications (7%). Hernia recurrences were observed in 17 patients (4%). No statistically significant differences on outcome were found between different surgeon experience (< 40 procedures, 40–80 procedures, > 80 procedures). Conclusion Implementation of TREPP seems not to be associated with a notable increase of adverse events. We were not able to detect a clear learning curve limit, potentially suggesting a relatively short learning curve among already experienced hernia surgeons compared to other guideline techniques.