State abbreviations

On July 1, 1963, the Post Office Department introduced the five-digit ZIP Code. At the time, most addressing equipment could accommodate only 23 characters (including spaces) in the bottom line of the address. To make room for the ZIP Code, state names needed to be abbreviated. The Department provided an initial list of abbreviations in June 1963, but many had three or four letters, which was still too long. In October 1963, the Department settled on the current two-letter abbreviations. Since that time, only one change has been made: in 1969, at the request of the Canadian postal administration, the abbreviation for Nebraska, originally NB, was changed to NE, to avoid confusion with New Brunswick in Canada.

A list of state abbreviations since 1831 is provided below. A more complete list of current abbreviations, including all U.S. possessions, is available online at

Promoting ZIP Codes in New York City, 1966

Promoting ZIP Codes in New York City, 1966
To allow space for the ZIP Code in the last line of an address, state names needed to be abbreviated. Previously, the Post Office Department preferred that state names be written in full, to avoid confusion.

MAY 2019

Postal abbreviations for states/territories

State/Territory 1831 1874 1943 June 1963 Oct. 1963 - Present
Alabama Al. Ala. Ala. ALA AL
Alaska -- Alaska Alaska ALSK AK
Arizona -- Ariz. Ariz. ARIZ AZ
Arkansas Ar. T. Ark. Ark. ARK AR
California -- Cal. Calif. CALIF CA
Colorado -- Colo. Colo. COL CO
Connecticut Ct. Conn. Conn. CONN CT
Delaware De. Del. Del. DEL DE
District of Columbia D. C. D. C. D. C. DC DC
Florida Fl. T. Fla. Fla. FLA FL
Georgia Ga. Ga. Ga. GA GA
Hawaii - -- Hawaii HAW HI
Idaho -- Idaho Idaho IDA ID
Illinois Il. Ill. Ill. ILL IL
Indiana Ia. Ind. Ind. IND IN
Iowa -- Iowa Iowa IOWA IA
Kansas -- Kans. Kans. KANS KS
Kentucky Ky. Ky. Ky. KY KY
Louisiana La. La. La. LA LA
Maine Me. Me. Maine ME ME
Maryland Md. Md. Md. MD MD
Massachusetts Ms. Mass. Mass. MASS MA
Michigan Mic. T. Mich. Mich. MICH MI
Minnesota -- Minn. Minn. MINN MN
Mississippi Mi. Miss. Miss. MISS MS
Missouri Mo. Mo. Mo. MO MO
Montana -- Mont. Mont. MONT MT
Nebraska -- Nebr. Nebr. NEB NB*
*to NE in 1969
Nevada -- Nev. Nev. NEV NV
New Hampshire N. H. N. H. N. H. NH NH
New Jersey N. J. N. J. N. J. NJ NJ
New Mexico -- N. Mex. N. Mex. NM NM
New York N. Y. N. Y. N. Y. NY NY
North Carolina N. C. N. C. N. C. NC NC
North Dakota -- -- N. Dak. ND ND
Ohio O. Ohio Ohio OHIO OH
Oklahoma -- -- Okla. OKLA OK
Oregon -- Oreg. Oreg. ORE OR
Pennsylvania Pa. Pa. Pa. PA PA
Puerto Rico -- -- P. R. PR PR
Rhode Island R. I. R. I. R. I. RI RI
South Carolina S. C. S. C. S. C. SC SC
South Dakota -- -- S. Dak. SD SD
Tennessee Te. Tenn. Tenn. TENN TN
Texas -- Tex. Tex. TEX TX
Utah -- Utah Utah UTAH UT
Vermont Vt. Vt. Vt. VT VT
Virginia Va. Va. Va. VA VA
Washington -- Wash. Wash. WASH WA
West Virginia -- W. Va. W. Va. W VA WV
Wisconsin -- Wis. Wis. WIS WI
Wyoming -- Wyo. Wyo. WYO WY

Sources: 1831, Table of Post Offices in the United States; 1874 and 1943, United States Official Postal Guide; June 1963, Postal Bulletin 20368; Oct. 1963, Post Office Department Publication 59, Abbreviations for Use with ZIP Code.