Electronic microchip implants were used to identify groups of crab-eating (Macaca fascicularis) and rhesus (Macaca mulatta) macaques. They were implanted in different body sites and monitored for up to fifteen months. One group of rhesus macaques was trained to present the wrist in which the microchip was placed, to enable it to be read easily with the scanner. An improved method of permanently identifying primates will lead to better record keeping and could benefit the animals’ welfare.