It used to serve Athlone between Galway and Dublin.
There's no Public Service Obligation to replace an axed bus route serving the midlands, according to the NTA.
The 706/706X Aircoach commute between Galway and Dublin, which stops in Athlone, was discontinued at the beginning of April.
That decision was taken as the service has not proven to be financially viable.
The National Transport Authority says the existing services in operation along the Galway to Dublin corridor via Ballinasloe, Athlone, and Maynooth meet the minimum service standard outlined in Connecting Ireland, and no immediate action is required to address the withdrawal of route 706.
It also says it will continue to monitor local demands for travel along the route.