COMMONWEALTH OF THE NORTHERN MARIANA ISLANDS
The people of the Northern Mariana Islands decided not to seek independence and negotiations for U.S. Territorial status were commenced culminating in the establishment of a Commonwealth in union with the U.S. The new administration commenced in 1978 under the name Commonwealth of the Northern Mariana Islands.
Postal Services continue to be provided by the U.S. Postal Service and only one additional Post Office has been established since 1978.
The following Post Offices are currently open in the Commonwealth of the Northern Mariana Islands:-
Saipan
Tinian San Jose Rural Branch
Saipan Capitol Hill Rural Branch
Rota
Saipan San Vicente Branch opened sometime prior to March 1994

Rota - the most Southerly Island - Only a few miles from Guam
The Only Postmark which includes the word "Commonwealth"
San Jose Rural Branch, Tinian Island

Capitol Hill - The site of the CNMI Government

San Vicente - the latest Post Office to open
It is on the East Coast of Saipan
To Federated States of Micronesia
To Republic of the Marshall Islands