The Pink Line will start its trial run on Tuesday, with free rides to be offered to passengers in September and October, said a source from the Mass Rapid Transit Authority of Thailand (MRTA).
The trial run is set to begin after the Northern Bangkok Monorail (NBM), which was granted the concession to operate the line, finished its systems test run from the depot station to the Nonthaburi government complex station. The entire line covers 30 stations.
The Pink Line will offer free rides for the next two months before opening as a commercial service in November. The opening comes earlier than planned, the source said.
Construction of the MRTA's Pink Line, linking Khae Rai Station at one end to Min Buri Station on the other, has been underway since 2016, with the government helping the MRTA with the land appropriation.
The 34.5-kilometre-long straddle monorail line starts at Nonthaburi Civic Centre Station, which is connected to the MRT Purple Line, and ends at Min Buri Station, which will be connected with the Orange Line that is currently under construction.
Meanwhile, also starting on Tuesday, services along the State Railway of Thailand's (SRT) Red Line will begin earlier, with the first trains leaving the depot at 5am instead of 5.30am, said Suthep Punthupeng, CEO of SRT Electrified Train Co.
The decision was taken in light of growing ridership, as well as to help early morning travellers get to and from Don Mueang airport, he said.
SRT has also reduced the service headway along the Red Line, with trains now scheduled to arrive every 10 minutes between 7am-9.30am and 5pm-7.30pm on the section between Krung Thep Aphiwat Central Terminal and Rangsit.
Trains will arrive every 15 minutes outside rush hour, he said.
On the section between Krung Thep Aphiwat Central Terminal and Taling Chan, also known as the Light Red Line, trains will still arrive every 20 minutes, according to Mr Suthep.