When Ferrocarriles Argentinos was dissolved and the long-distance services closed by the government of Argentina (with Carlos Menem as president), the freight lines of the FC Sarmiento were given in concession to Ferroexpreso Pampeano.

After the rail disaster of 2012, the government revoked its contract with TBA[1] and the services were taken over by a newly created state-owned company, SOFSE, which later renewed the urban parts of the network with new rolling stock and infrastructure.

During its first years the service covered a 10 km path from the Plaza Del Parque station (where the Teatro Colón is located nowadays) to La Floresta, then part of San José de Flores Partido.

Therefore, the BAWR was sold to British company "The Buenos Aires Western Railway Limited", mostly known for its Spanish form "Ferrocarril del Oeste".

By 1945 the British and French companies were seriously affected by the World War II, beginning contacts with the Government of Argentina to sell their railway lines that still operated in the country.

The Ferrocarril del Oeste received the name "Domingo Faustino Sarmiento", honoring the memory of educator and former President of Argentina born in San Juan Province (one of the regions served by the railway).

It was run through a tunnel by wooden-bodied coaches between Caballito and the recently inaugurated "1° de Marzo" station, located on the crossing of the Buenos Aires Port railway and Cangallo street, in Puerto Madero.

Other branches closed were Villa Luro-Versalles (on 5 October 1952) and the "Basílica de Luján" In 1953 the first electronic warning devices were installed on the Boyacá street level crossing of Flores district, having been the first in Argentina.

Under plans announced in 2006, a 33 km tunnel would be bored between Moreno and Caballito in order to replace the surface alignment of the Sarmiento commuter route.

According to the Minister of the Interior and Transport, the first stage was to cost 11·5bn pesos, removing many level crossings which would "avoid many accidents and much loss of life".