Single port surgery of rectal tumors may be associated with a shorter learning curve and fewer costs than transanal endoscopic microsurgery. The authors aimed to select the most optimal single access port for transanal employment. Four single access ports (GelPOINT, TriPort, SSL Access System, and SILS) were tested in 2 pigs. Insertion feasibility and intraoperative features of each port were assessed. A rectal excision was attempted using the most suitable port. Insertion of GelPOINT was impossible. SILS and TriPort were easily inserted; however, insufficient stability demanded manual fixation. CO2 leaked through the TriPort trocar ports. Insertion of the 2-cm SSL Access System retractor was difficult, but pneumorectum and surgical circumstances were favorable. Single port transanal surgery may be a promising alternative for transanal endoscopic microsurgery. The SSL Access System was found the most suitable for this indication in a porcine model.