Though the Confederacy terminated franking privileges on March 15, 1861, provision was made for the postmaster general and various other Post Office Department officials to send official mail free-of-charge when endorsed “Official Business” over their signatures. In most cases, printed envelopes prepared especially for this purpose were used, and they are referred to as 'Officials'. When used for private correspondence, regular postage was due.
There were two different groups of official envelopes. The primary group was for the Post Office Department in Richmond, Virginia, and the other for the Trans-Mississippi agency in Marshall, Texas. Used but unsigned imprinted official envelopes generally were hand-carried or bore Confederate stamps to pay the postage.