The majority of states, including Texas, prohibit long combination vehicles. Additionally, long combination vehicles have been banned on federal highways since 1991.
States that permit long combination vehicles distinguish them not by the number of trailers they pull but by the length of the trailers. States that permit double and triple trailers also restrict them to specific routes.
States that allow doubles less than 100 feet – Washington, Oregon, Utah, Wyoming, South Dakota, Alaska, and Nebraska.
States that allow double up to and over 100 feet – New York, Florida, and Massachusetts.
States that allow doubles less than 100 feet and triples – Oregon, Nevada, Idaho, Montana, and Utah.
States that allow doubles up to and over 100 feet and triples – Oklahoma, Ohio, Indiana, Kansas, Missouri, Colorado, North Dakota, South Dakota, and Montana.