A new persistent groin pain is reported by a significant number of patients following laparoscopic totally extraperitoneal hernia repair (TEP). Mesh fixation has been implicated as a possible cause, but is widely considered essential for mesh stabilization and early recurrence prevention. This study investigates whether any association exists between mesh fixation by metal tacks and the incidence of new groin pain or early hernia recurrence. A prospective multicenter double-blinded randomised trial was conducted between December 2004 and January 2006. Standardized TEP repair was performed with a rectangular 10 × 15cm polypropylene mesh. Hernia were randomized to either mesh fixation by metal tacks or left entirely unfixated. Clinical review by physical examination was performed by a separate blinded surgeon after a minimum of six months, with another review planned after two years. The incidence of new groin pain and recurrence were compared. Five hundred herniae in 360 patients were entered into the study. At the first wave of clinical follow-up (median eight, range 6–13 postoperative months) a new pain was reported by 38 versus 23% ( p = 0.003), occurring at least once a week in 22 versus 15% ( p = 0.049), or several times per week in 16 versus 8% ( p = 0.009) for fixated versus unfixated repairs, respectively. Patients with bilateral repairs were five times more likely to report the unfixated side being more comfortable ( p = 0.006). There was one recurrence in the fixated group (1/247) whilst none have yet occurred in the unfixated group. Fixation increased operative costs by approximately 375 AUD. Mesh fixation in TEP is associated with increased operative cost and chronic pain but no difference in the risk of hernia recurrence at six months was observed. [ABSTRACT FROM AUTHOR]