A Department of Defense Activity Address Code is a six-character alphanumeric code assigned to any unit that has the authority to spend DoD funds or control DoD assets. The codes are used to methodize contracting and auditing procedures between U.S. Federal Departments and private contractors. The first positions of the DoDAAC signify ownership of a specific service or agency. An alpha character indicates a DoD activity, and a numerical character denotes an external agency or contractor.
Examples of initial characters in DoDAACs assigned to the Army, Navy, Marines and Air Force are A, N, M and F respectively. The U.S. Postal Service is 18, and the Central Intelligence Agency is 56. A complete list is available in the DoDAAD Series Table at the Defense Logistics Management Standards Office page of the Defense Logistics Agency website.
There are more than 300,000 DoDAACs in existence, which are used in approximately five billion transactions every year. Each DoDAAC is a unique identifier to a file containing over 100 pieces of information about the specific unit, agency or contractor. Such information includes a physical address, delivery address, billing address, points of contact, relevant authority and date of termination if the DoDAAC is awarded only for a temporary contract.