The TransBus Enviro300 was launched in 2001 by TransBus International, becoming the first member of the Enviro range; with the collapse of TransBus in 2004, successors Alexander Dennis took over production and rebranded the Enviro300 as the Alexander Dennis Enviro300.
A common design was used primarily that the bus has a single-curvature windscreen with a peaked roof dome and a separately mounted destination sign.