It is administered by the Government of Mexico City and carries approximately 400,000 passengers per day on more than 100 routes.

Public bus service in the Mexico City metropolitan area was provided by several private concessions starting from 1916,[3]: 249  including the Lomas de Chapultepec Primera Clase, which was founded in 1942.

[3]: 255  On May 3, 1989 the Ruta 100 worker's union Sindicato Único de Trabajadores de Ruta 100 (SUTAUR 100) went on strike, asking for double their existing wages; the negotiated settlement included a 14% wage increase but also the elimination of approximately 1⁄3 of its 20,000 jobs.

[3]: 258 [5] In 1994, Ruta 100 operated approximately 2,900 buses on 210 routes over a 7,500 km long (4,700 mi) network, carrying 2.9 million passengers per day.

[3]: 259–260  With the demise of Ruta 100, part of the operator's fleet and employees were transferred to the Servicio de Transportes Eléctricos (STE) while the former network was operated by the Consejo de Incautación (Board of Seizure) under the Sistema Temporal de Transporte (STT; Temporary Transportation System), carrying 544 thousand daily passengers using 830 buses on 75 routes;[6]: 78  the STT fleet was inherited by RTP when it was formed in January 2000.