The operational rolling stock of São Paulo Metropolitan Trains is composed different compositions of 12 different series, produced between 1956 and 2024, and it is the largest rolling stock of Brazil, split between Companhia Paulista de Trens Metropolitanos and ViaMobilidade. The Company are passing by a deep stock modernization since 2007, which aims to withdraw the whole old trains. The modernization is being done also in the lines. Although, the biggest part of the modernization works is suffering delays since the initial prediction of completion was exceeded in 2012 and, because of that, the Company has been withdrawing the old stock gradually. The trains are identified by serial numbers and they are with your visual communication being updated to the new red pattern in so far as they undergo into general review, which occurs after a certain mileage. Older trains already passed by several visual modifications, internal and external, besides small, medium and large reforms. All CPTM trains have a 1,600 mm broad track gauge and overhead catenary electric transmission of 3 kV DC. All lines operates with ATC system, however, Lines 7, 9 and 12 are being modernized to ATO, and Lines 8, 10, and 11 to CBTC. All operating compositions have the two new systems when the new signalling works.

The Companhia Paulista de Trens Metropolitanos (CPTM) is a rapid transit and commuter rail company owned by the São Paulo State Department for Metropolitan Transports. It was created on 28 May 1992, from several railroads that already existed in Greater São Paulo, Brazil.