The fares for the new Onnut-Bearing and Wong Wian Yai-Bang Wa sections of the BTS skytrain will be 15 baht, starting Saturday.
The increases are in effect the elimination of a promotional discount offered when the two sections opened.
Bangkok Metropolitan Administration (BMA) governor Assawin Kwanmuang signed the announcement on Friday, said Suthon Anakul, deputy director of the BMA's Traffic and Transport Office.
"The fares are now 10 baht on both routes. Since the BMA needs more budget for the mass transit management cost of 600 million baht a year, we need to charge 15 baht for both sections," Mr Suthon said.
The change will add 30% more income to BMA's coffers. With the extra money, City Hall will need 400 million baht instead of 600 million a year to hire Bangkok Mass Transit System Plc (BTS) to operate the routes.
The fares for both sections were set at 15 baht from the start. In May 2013, then BMA governor MR Sukhumbhand Paribatra cut it to 10 baht in keeping with his election pledges.
Both sections extended from the main Green Line, which consists the Sukhumvit Line and the Silom Line (see chart). City Hall paid for the construction costs and is hiring BTS to operate the extensions and sharing revenue with it.
The On Nut-Bearing section of the extended Sukhumvit line has five stations: On Nut, Bang Chak, Punnawithi, Udom Suk, Bang Na and Bearing.
The Wong Wian Yai-Bang Wa section of the Silom Line also has five stations: Wong Wian Yai, Pho Nimit, Talat Phlu, Wutthakat and Bang Wa.
A map of the BTS Green Line. (Wikimedia/Zeddlex)