New York City Transit NovaBus LFS 1254 M15 SBS
An articulated bus (either a motor bus or trolley bus) is an articulated vehicle used in public transportation. It is usually a single deck design, and comprises two rigid sections linked by a pivoting joint. This arrangement allows a longer legal overall length than single-decker rigid bodied buses, and hence a higher passenger capacity, while still allowing the bus to maneuver adequately on the roads of its service route.

Around the English-speaking world, articulated buses have acquired several different synonyms that allude to their articulated design, such as bendy buses, bending buses, tandem buses, stretch buses, double buses, banana buses, slinky buses, wiggle buses,catepillar buses, accordian buses or vestibule buses. Due to their high passenger capacity, articulated buses are often used as part of bus rapid transit schemes, and can include mechanical guidence.

Used almost exclusively on public transport bus services, articulated buses are approximately 18 metres (59 ft) in length; standard rigid-construction buses are usually 11 to 14 metres (36 to 46 ft). The common arrangement of an articulated bus is to have a forward section with two axles leading a rear section with a single axle, with the driving axle mounted on either the front or the rear section. Some articulated bus models have a steering arrangement on the rearmost axle which turns slightly in opposition to the front steering axle, allowing the vehicle to negotiate turns in a crab-like fashion, similar to hook and ladder fire trucks operating in city environments. A less common variant of the articulated bus is the bi-articulated bus, where the vehicle has two trailer sections rather than one. Their capacity is around 200 persons, and their length about 25 metres (82 ft).