[6] During Holy Week, a public holiday in the Philippines, the rail system is closed for annual maintenance, owing to fewer commuters and traffic around the metro.

[8] During the construction of the first line of the Manila Light Rail Transit System in the early 1980s, Electrowatt Engineering Services of Zürich designed a comprehensive plan for a metro service in Metro Manila.

The plan—still used as the basis for planning new metro lines—consisted of a 150-kilometer (93 mi) network of rapid transit lines spanning all major corridors within 20 years.

In 1997, MRTC entered into a turnkey contract with Sumitomo Corporation and Mitsubishi Heavy Industries for the line's construction.

[20] Sumitomo and Mitsubishi subcontracted EEI Corporation for the civil works, while a separate agreement was signed with ČKD Tatra for the rolling stock.

[20] Funding for the project was sourced from loans from various banks in Japan and the Czech Republic, with the help of JP Morgan.

[20] The Department of Transportation and Communications (later the Department of Transportation) hired SYSTRA for the consultancy services, while the MRTC hired ICF Kaiser Engineers and Constructors to provide program management and technical oversight of the services for the design, construction management, and commissioning.

[22] The Metro Manila Subway will have a platform length of 210 meters (689 ft 0 in) to accommodate eight-car trains.

As of February 1, 2012, folding bicycles are allowed to be brought into Line 3 trains provided that the wheels do not exceed more than 20 inches (51 cm) in diameter.

Electric multiple units will be introduced when Line 7 and the Metro Manila Subway opens.

The first-generation cars (numbered from either 000 or 3000), built by ČKD Tatra in Prague, Czech Republic, are currently being used in the system.

However, the second-generation trains were met with controversy, causing it to not be regularly deployed in revenue service.

[32] It would be powered from overhead lines with a voltage of 1,500 volts, similar to the Makati Subway.

[39] The magnetic tickets have since been replaced with the Beep, a contactless smart card which is being used since 2015 in all Manila LRT and MRT lines.

The MRT Line 7 is a 22-kilometer (14 mi), 14-station heavy rail line running in a northeast–southwest direction, starting from the San Jose del Monte station in Bulacan to the North Triangle Common Station in Quezon City.

[43] The Metro Manila Subway is a 36-kilometer (22 mi) underground heavy rail line.

Funded by a loan from Japan, construction began in 2019 and is slated to partially operate by 2025.