An express bus service (also known as commuter bus service) is a bus service that is intended to run faster than normal bus services between the same two commuter points.
Express buses operate on a faster schedule by not making as many stops as normal bus services and often taking quicker routes, such as along freeways.
The fare on an express bus service may be higher than normal parallel services, for the quicker service. Many express buses require passengers to purchase tickets before boarding the bus, speeding up the service.
In many cases, an express bus service is identified by a letter before or after the regular route number. For example in Sydney, the letters L (as in L90), E (as in E70) and X (as in 610X or X84).