The NFTC began issuing its Memorandum series in 1947. The Memoranda were prepared for the Board by its Divisions and Committees and tended to be more substantial and more focused than the Bulletins. Memoranda were numbered sequentially with a new numbered series usually beginning after 10,000. In later years, there were parallel series with and without an "M" prefix, plus other collections of memoranda on particular subjects.

The Tax Committee accounts for the largest number of memoranda during the 1950s, 1960s and 1970s. These include the texts of tax treaties with numerous trading partners granting equal tax status to each country's nationals and companies. During the 1950s, the memoranda include reports and speeches delivered at the annual National Foreign Trade Conventions, some of which have been cataloged individually. The memoranda also include periodic reports on the cost of living in foreign countries issued by the U.S. State Department.