Bustitution

A rail replacement bus service uses buses to replace a passenger train service either on a temporary or permanent basis. The train service that is replaced may be of any type such as light rail, tram, streetcar, commuter rail, regional rail or heavy rail, intercity passenger service. The rail service may be replaced if the line is closed due to rail maintenance, a breakdown of a train, a rail accident, strike action, or if the rail service is not economically viable.

Terms for a rail replacement bus service include bustitution (a portmanteau of the words "bus" and "substitution", may also be bustitute) and bus bridge. Substitution of rail services by buses can be unpopular and subject to criticism, so the term bustitution is often used pejoratively.

A similar concept in some ways is motorization, but that term more broadly refers to the rise of the automobile as well as bus transportation.

In Australia, a permanent or temporary rail-replacement service change is often referred to as bustitution.

Via Rail, the operator of the national passenger rail network, uses the term "bustitution" to refer to rail replacement with buses.

When train services operated by Transdev in Auckland train services are sometimes replaced by a bus, the resulting service is called Rail Bus. Historically, New Zealand Railways Road Services replaced many train routes with buses.

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