Lavatory unit

Lavatories on-board a vehicle, and in particular to a lavatory unit for use by persons with reduced mobility on-board a vehicle are described. The lavatory unit includes a lavatory housing structure enclosing a lavatory interior space, a door opening in the lavatory housing structure, a toilet assembly inside the lavatory interior space, and a transition seating support for a user. The transition seating support provides a first transfer position and a second transfer position. In the first transfer position, in an open door state the transition seating support is directly accessible for a person sitting in a wheelchair that is located at least partly outside the lavatory unit such that the person can transfer to the transition seating support and vice versa, and in the second transfer position, a person sitting on the transition seating support can transfer to the toilet assembly and vice versa.