Salvatore Fornatora began operating buses in Queens since 1919, with his first route (today's Q19 route) connecting 103rd Street-Corona Plaza on the recently opened Corona Line in Corona with Flushing. The Corona terminal was moved to Astoria in 1928, when the Corona Line was extended to Flushing, and the company (then the Woodside-Astoria Transportation Company) was also operating several other routes in the Astoria-Woodside-Maspeth area by 1930.
The new Triboro Coach Corporation was incorporated on April 10, 1931 running the Q18 and Q24, and on September 24, 1936 it acquired a city franchise for nine routes in northwestern Queens (the "Long Island City zone"). After World War II, Triboro was acquired by the stockholders of Green Bus Lines, after financial difficulties, but continued to operate independently. Major expansions were made in 1956 between Woodside and Rockaway Park (replacing the Long Island Rail Road's Rockaway Beach Branch, out of service since 1950) and in 1961, when it acquired the Q72 (then the B72) from the New York City Transit Authority. Five express routes to Manhattan were initiated in the 1970s and 1980s: the QM10 in 1970, QM11 in 1971, QM12 in 1975, and QM22, QM24, and QM24W in June 1988.
In addition to diesel powered buses, Triboro housed a CNG fueling facility and CNG powered buses. CNG fueling was installed in 1994 to be used for orders of TMC RTS-06 CNG buses and later Orion V CNG buses that were ordered in conjunction with identical buses used by Command Bus Company and Queens Surface Corporation (now Spring Creek Depot and College Point Depot respectively). The facility remained following MTA Bus takeover when the former Triboro Coach facility became the LaGuardia Depot. However, the facility was destroyed and shut down in April 2006 (only 2 months after the MTA Takeover) following an explosion within one of the natural gas lines and destroyed a former Triboro/ ex-Jamaica Bus RTS-04. Since then, all of the ex-Triboro CNG buses were transferred to Spring Creek and College Point Depots and ran from there up until their retirement.
Just prior to MTA Bus takeover, Triboro Coach operated the following routes. Most of these continue to be based out of the company's former facility:
- Q18 Astoria - Maspeth, via 30th Avenue (Formerly Q18 Astoria-Woodside and Q24 Woodside-Maspeth; combined into Q18)
- Q19 Astoria - Flushing, via Astoria Boulevard
- Q23 East Elmhurst - Forest Hills via 108th Street (acquired in 1936 from North Shore Bus Company)
- Q29 Jackson Heights - Glendale via 80th Street (acquired in 1936 from Kings Coach Company)
- Q33 Jackson Heights - LaGuardia Airport Central Terminal (acquired in 1936 from Municipal Motorbus Company) via 82nd/83rd Streets
- Q38 Eliot and Penelope Avenues (acquired in 1936 from Affiliated Bus Transit Corporation)
- Q39 Long Island City - Ridgewood, via Forest Avenue (acquired in 1936 from National City Bus Lines)
- Q45 Jackson Heights - Juniper Valley via 69th Street
- Q47 Jackson Heights - LaGuardia Airport Marine Air Terminal via 69th Street and 80th Street
- Q49 (Formerly Q19B) Jackson Heights - East Elmhurst via 35th Avenue
- Q53 Woodside - Rockaway Park (limited stop) (established in 1956)
- Q69 (Formerly Q19A) Long Island CIty - Woodside via 21st Street & Ditmars Blvd.
- Q72 LaGuardia Airport - Rego Park via Junction Boulevard (acquired in 1961 from New York City Transit Authority)
- QM-10 Lefrak City Express via 6th Avenue or 3rd Avenue
- QM-11 Forest Hills - LeFrak City - Wall Street
- QM-12 Forest Hills Express via 6th Avenue or 3rd Avenue
- QM-22 Jackson Heights Express via 6th Avenue or 3rd Avenue (discontinued in 2010)
- QM-24 Glendale Express via 8th Avenue or 3rd Avenue
- QM-25 (Formerly QM-24W) Glendale - Wall Street Express
- Triboro Coach Corporation (accessed January 19, 2007; Revived November 4, 2013)
- NYCDOT - Privately Operated Bus Service (as of early-to-mid 2000s, accessed January 19, 2007)
- New York Times, Long Island City Zone Taken by One Bus Line, January 4, 1936, page 17
- Triboro Coach Corporation (via the Internet Archive)