State Abbreviations and State Postal Codes Since the Postal Service instituted ZIP codes and their accompanying state postal codes in 1963, the two-letter abbreviations have steadily gained popularity. Though it is usually preferable to write out the full name, space constraints often require use of an abbreviation. When you have to use an abbreviation, the standard abbreviation is strongly preferred. The postal code abbreviation should be used only in mailing addresses. Fact Monster/Information Please® Database, © 2008 Pearson Education, Inc. All rights reserved.
|