Abstract Background Laparoscopic transabdominal preperitoneal (TAPP) herniorrhaphy provides an opportunity to definitively evaluate both inguinal areas without the need for additional dissection. We aimed to establish the rates and contributing patient factors to errors in the preoperative assessment. Methods A retrospective review of consecutive patients undergoing laparoscopic TAPP herniorrhaphy at 2 tertiary-care centers. Preoperative history and physical examination were used to classify the presence of hernia as “definite,” “questionable,” or “negative.” Any discrepancies between preoperative and intraoperative findings were viewed as errors in preoperative assessment. Results Two hundred sixty-two patients underwent 328 laparoscopic TAPP hernia repairs. Of the 283 hernias diagnosed as “definite” preoperatively, 276 were confirmed at operation (97.8%). An additional 19 of 173 (11.0%) clinically unrecognized hernias were repaired at the time of surgery. Overall, our approach avoided unnecessary groin explorations and/or repairs in up to 16.4% patients and may have prevented inappropriate delays of herniorrhaphy in up to 19.8% of patients. The sensitivity, specificity, and positive predictive value of the clinical assessment of inguinal hernia were 94.5%, 80%, and 88.9%, respectively. Symptom and/or examination findings of inguinal mass were the only significant independent predictor of accuracy ( P < .001). Conclusion A high rate of discordance exists between the preoperative clinical assessment and true presence of inguinal hernias. Given the unique ability of laparoscopy to accurately evaluate the contralateral side and the limited added morbidity of bilateral repair, TAPP herniorrhaphy is beneficial in avoiding unnecessary explorations and allowing timely repairs in patients with occult inguinal hernias.