North American Industry Classification System (NAICS) 1997

• 48-49 - Transportation and Warehousing

491 - Postal Service

This subsector comprises establishments primarily engaged in operating the postal service. Establishments of the Post Office, other than those primarily engaged in providing courier services, are classified in this industry, as well as establishments that carry on one or more functions of the postal service on a contract basis, except the delivery of mail in bulk.