The Authority supplies water, on a retail basis, to customers within its District which consists of the Town of Morristown, the Township of Morris, the Township of Hanover, and the Borough of Morris Plains. The Authority also sells minor amounts of water at retail rates to customers outside its District in portions of the Township of Harding pursuant to an agreement approved by the New Jersey Board of Public Utilities as necessary for the public convenience; and to a small number of customers in the Township of Chatham who were previously served by the Town of Morristown prior to the transfer of the water system to the Authority. In addition, the Authority sells bulk water, pursuant to bulk sale water agreements with the Borough of Florham Park, the Township of Parsippany Troy Hills and the Randolph Township Municipal Utilities Authority, for resale to customers outside the District who were previously served by the Town of Morristown prior to the transfer.

Under the bulk sale agreements, the Authority supplies bulk water for resale to each bulk service customer for an initial term of five years which is automatically renewable for successive one year periods unless terminated by either party on twelve months' notice. All existing agreements are in the automatic renewal phase.