Central Japan Railway (JR Central) and West Japan Railway (JR West) said Wednesday they will start offering Supreme Class premium private compartments on their bullet trains on Oct. 1.A private compartment for two passengers, to be built in the seventh car of the Tokaido and Sanyo Shinkansen train sets, will cost ¥60,790 per person for a one-way trip between Tokyo Station and Shin-Osaka Station in Osaka. It is ¥41,400 more than the price of a Green Car premium seat.Single-user compartments will be built in the 10th car, and semiprivate compartments will be rolled out in fiscal 2027, which begins next April.