The FAA allows airlines to decide whether to fly planes with broken restrooms, though other regulations do require restrooms in some instances. Consumer rules imposed by the U.S. Department of Transportation require airlines to provide consumers with access to working restrooms during excessive ground delays.

Yes, a plane can legally fly with one or more inoperable bathrooms, provided it meets the requirements of the airline's Minimum Equipment List (MEL). In 2026, FAA and EASA regulations allow for "deferred maintenance" on lavatories if the remaining functional bathrooms meet a specific ratio for the number of passengers on board. For example, on a long-haul flight, a wide-body jet with 8 bathrooms might be allowed to fly with 2 of them out of service. However, under the Air Carrier Access Act, if a flight has only one aisle, it must include at least one accessible lavatory if one was originally provided. If all bathrooms on a plane are inoperable, the flight is generally grounded or diverted, as it would violate basic passenger welfare and hygiene standards. Pilots must document any "MEL items" in the flight log, and passengers are often notified if bathroom access is limited.