Selected Singapore residents will hail the taxis using a smartphone app, and rides will be free during the trial, US-based nuTonomy said.
A nuTonomy engineer will travel in each car during the trial, "to observer system performance and assume control if needed", the company said.
NuTonomy is working in partnership with the Singapore Land Transport Authority to develop the commercial autonomous vehicle service. It has configured a fleet of Renault Zoes and Mitsubishi i-MiEV electric vehicles for autonomous driving, it said.
The company has been testing the cars in the one-north business district since April. It will use the trial to collect data on software performance, vehicle routing efficiency, the booking process and the overall passenger experience, it said.
NuTonomy plans to launch a commercial "robo-taxi" service in Singapore in 2018, it said.
The company also operates self-driving cars in Michigan, US, and in the UK where it tests software in partnership with manufacturers such as Jaguar Land Rover, it said.