It connects Sinsa station and Gwanggyo station in 42 minutes, a feat achieved by being the first line to operate South Korea's next-generation subway car travelling at over 90 km/h (56 mph), with the fastest average speed of any subway line in the country.

Phase 2 opened on 30 January 2016 added 6 stations to the south, extending the line to serve Yongin's Suji-gu and Suwon's Gwanggyo New City.

[7] The price to ride the Shinbundang Line is higher than standard fare for the rest of the Seoul subway system.

[15] Because part of the line lies inside the Yongsan Garrison, the phase was split into two sections.

It was unclear if this idea has been scrapped or pushed back for a later reevaluation[18] but resurfaced as a March 2012 campaign promise by Hong Sa-duk to expand the line near Gyeongbokgung Station.

However, the last train to Gwanggyo departs at 24:26 on weekdays, cut to 23:48 on weekends, with the remainder going until Jeongja station only.

The SBL Line signal system is based on state-of-the-art communications-based train control (CBTC) technology, utilizing two-way digital radio communications between intelligent trains, and wayside equipment, and a network of ATS/ATO computers designed for very high system reliability and availability.

[10][21][22] Jungbunaeryuk KTX Although initially planned to be opened simultaneously with the Sinsa-Gangnam extension, due to the extension from Sinsa to Yongsan potentially sharing tracks with the newly approved GTX A line towards Ilsan, construction on this section has been delayed.

The stations' locations will be determined when the Yongsan Garrison moves out and the freed space becomes a public park.