This line would link the Din Daeng housing community areas, Bangkok City Hall 2, Makkasan Station (for the Suvarnabhumi Airport Rail Link), and the business area along Sathon Road.

The total distance of the route is approximately 9.5 km (5.9 mi) with 9 stations and an estimated 320,000 passengers per day.

In 2013, the Bangkok Metropolitan Administration took over responsibility for the Light Blue line project.

BMA transferred the project to the Mass Rapid Transit Authority of Thailand (MRTA) on December 27, 2024, as it is believed that consolidating the project under a single owner will enable better control of fare prices, preventing them from becoming excessively high.

[1] Given delays in 2013 and 2014 with tendering other priority mass transit lines related to the political crisis in Thailand, it is highly unlikely that the Light Blue line will be considered by either the BMA or the Mass Rapid Transit Authority for many years.