In fiscal 1999, the Jōsō Line carried an annual total of 14.16 million passengers (38,000 per day), making it the busiest non-electrified private line in Japan.

[1] The Jōsō Railway opened the line on 1 November 1913.

[citation needed] Originally all single-track, 17.5 kilometres (11 mi) of the line was doubled between Toride and Mitsukaidō by 15 November 1984.

[1] However, due to the limitations brought by the Kakioka Magnetic Observatory located in Ishioka, this line is still not electrified.

The KiHa 310 vehicles are scheduled for withdrawal in July 2023.