This study evaluated the efficacy of two potential zero‐withdrawal anesthetics, Benzoak (20% benzocaine; 50, 60, and 75 mg/L) and Aqui‐SE (50% eugenol; 50, 60, and 75 mg/L) compared with tricaine methanesulfonate (MS‐222; 55, 80, and 100 mg/L), to anesthetize Rainbow Trout Oncorhynchus mykiss for PIT tag implantation surgery. In general, higher doses resulted in faster induction time to stage 4 anesthesia (defined by the cessation of reflex activity). At 204 s, the time to stage 4 anesthesia was slowest using MS‐222 at 55 mg/L, followed by 50 mg/L of either Benzoak and Aqui‐SE, which in turn were significantly slower to induce this level of anesthesia than were Benzoak or Aqui‐SE at 60 or 75 mg/L or MS‐222 at 80 mg/L. At 100 mg/L, MS‐222 had the quickest time, 57 s, to stage 4 anesthesia. Time to recovery was longest for Rainbow Trout exposed to any concentration of Aqui‐SE and shortest for MS‐222, and recovery times from Benzoak were intermediate. Although Rainbow Trout length and weight varied significantly among the treatments, time to anesthesia and recovery were more dependent on the anesthetic and concentration used. In our opinion, doses of either Benzoak or Aqui‐SE of greater than 60 mg/L will induce rapid anesthesia and provide relatively quick recovery times for adult Rainbow Trout.Received July 27, 2012; accepted January 10, 2013