Anecdotal evidence suggests that bumper plates impact lifts in powerlifting and weightlifting different than standard cast iron plates, but very few studies have investigated how bumper plates affect the biomechanics of any lift. The aim of this study was to examine if there were any differences in bench press biomechanics when comparing lifts with bumper versus standard plates. Eleven resistance-trained participants performed the bench press using both bumper and standard plates at 70%, 80%, and 90% 1RM. The participants were blinded to whether they were lifting bumper or standard plates by boxes covering the plates on the barbell. The participants had a 1RM of 99.51 ± 32.90 kg, and lifted 71.68 ± 23.28 kg at 70% 1RM, 81.29 ± 26.23 kg at 80% 1RM, and 91.61 ± 30.10 kg at 90% 1RM. Motion data was captured by an eight-camera motion capture system and EMG data was recorded for the anterior deltoid, pectoralis major, and triceps brachii. Repeated measures ANOVAs showed a significant main Weight effect for Time-Under-Tension (TUT) (p < 0.001), Total Work (TW) (p < 0.001), and EMG (p < 0.001), and a significant Weight x Joint interaction effect for average joint moment (p < 0.001), impulse (p < 0.001), and peak joint moment (p <0.001). However, there were no significant differences observed between the different weight plates for any of the measures. The main findings of the study suggest that there are no biomechanical differences between using bumper plates or standard plates during the bench press lift.