SoftBank Autonomous Driving Bus Project in Yokosuka City

SoftBank Autonomous Driving Bus project was formally introduced in Yokosuka City, Kanagawa Prefecture, bringing together Yokosuka City, Keihin Kyuko Bus Corporation, and SoftBank Corp. to showcase their latest autonomous bus demonstration. The initiative highlights Japan’s push to transform urban mobility through advanced self-driving public transport solutions.
SoftBank Autonomous Driving Bus Demonstration in Yokosuka
The partners presented the autonomous driving bus trial to the media on January 13, outlining how the service began operations in December 2025 using Level 2 driver-assistance technology. The demonstration phase is designed to evaluate safety, performance, and real-world operation of automated buses on city routes.
Roadmap Toward Level 4 Autonomy
Under the current plan, the SoftBank Autonomous Driving Bus is expected to transition to Level 4 autonomous operation under specific operating conditions by the end of March 2028, which corresponds to the close of Japan’s FY2027. This upgrade will allow the buses to operate without human drivers in defined environments.
Key milestones include:

• Level 2 autonomous bus operations starting December 2025

• Level 4 conditional autonomous driving targeted by March 2028

• Commercial platooning operations planned for FY2028

Consortium for Yokosuka Autonomous Bus Routes
To implement a full-scale autonomous route bus system, Yokosuka City, Keihin Kyuko Bus, and SoftBank have created a dedicated consortium. This group has been selected as part of a national government program supporting the social implementation of autonomous driving technologies for regional public transportation.
The initiative is part of a broader effort to secure, maintain, and enhance local mobility while reducing dependence on conventional driver-based services.
Platooning Technology and Previous Development
The project also includes plans to introduce platooning, where two autonomous buses travel in coordinated formation to improve traffic flow and efficiency. This capability will be commercialized in FY2028 as part of the Yokosuka deployment.
The consortium is leveraging experience gained from the earlier development of autonomous driving and platooning Bus Rapid Transit systems created jointly by SoftBank and West Japan Railway Company. In that program, multiple self-driving vehicles operated in formation on dedicated roadways, forming the technical foundation for the Yokosuka rollout.
By combining municipal support, public transport expertise, and advanced mobility technology, the SoftBank Autonomous Driving Bus project is positioned to become a key reference model for future autonomous public transportation in Japan.