The purpose of this study was to determine whether there is a difference in physical activity assessment between a wrist‐worn accelerometer at the dominant or non‐dominant arm. The secondary purpose was to assess the concurrent validity of measures of physical activity from the wrist‐worn accelerometer and the waist‐worn accelerometer. Forty adults wore three accelerometers simultaneously, one on the waist and one each on the non‐dominant wrist and dominant wrist, respectively, for 24 consecutive hours of free‐living conditions. Data were uploaded from the monitor to a computer following a 1‐day test period. There were no significant differences in physical activity when comparing the dominant versus the non‐dominant wrist, regardless of axis (P>0·05). Mean daily accelerometer output data from both wrists were strongly correlated with average counts per minute from the ActiGraph worn around the waist (r = 0·88, P<0·001). Findings suggest that the choice to wear the accelerometer on the non‐dominant or dominant wrist has no impact on results. Data from this study contribute to the knowledge of how to best assess physical activity habits.