State Abbreviations
Until 1963 the
Post Office Department preferred that state and territorial names be written
out in full to avoid confusion, but accepted the popular public practice of
abbreviation.
The
Department published lists of preferred state abbreviations in the 1831 Table of Post Offices in the United States
and in the United States Official Postal
Guide, first published in 1874. Most
of the preferred abbreviations in 1874 remained the same for nearly the next 90
years.
On July 1, 1963,
the Post Office Department implemented the five-digit ZIP Code, which was
placed after the state name in the last line of an address. To provide room for
the new code in the address line, the Department published an initial list of
state abbreviations in the June 27, 1963, issue of the Postal Bulletin. Many of these
initial abbreviations consisted of four letters.
Four months
later, in October 1963, the Department published the now-familiar list of two-letter
state abbreviations in Publication 59, Abbreviations for Use with ZIP Code. Two-letter abbreviations were:
. . . provided by the
Post Office Department as an aid to mailers in accommodating ZIP Codes within
the usual City-State line of addresses.
The abbreviations are based on a maximum
23-position line, because this has been found to be the most universally
acceptable line capacity basis for major addressing systems.
The
implementation of two-letter state abbreviations was gradual; initially they
were intended for optional use only by large business mailers in conjunction
with ZIP Codes.
To date, only
one change has been made to the abbreviations issued in October 1963. In November 1969, at the request of the
Canadian postal administration, the abbreviation for
Preferred
Abbreviations for States/Territories
|
1831 |
1874 |
1943 |
6/1963 |
10/1963 |
---|---|---|---|---|---|
|
Al. |
|
|
|
|
|
-- |
|
|
ALSK |
AK |
|
-- |
|
|
|
AZ |
|
Ar. T. |
|
|
|
AR |
|
-- |
|
|
|
CA |
|
-- |
|
|
|
CO |
|
|
Conn. |
Conn. |
|
CT |
|
De. |
|
|
|
DE |
|
D. C. |
D. C. |
D. C. |
DC |
DC |
|
Fl. T. |
|
|
|
FL |
|
|
|
|
GA |
GA |
|
-- |
-- |
|
HAW |
HI |
|
-- |
|
|
IDA |
ID |
|
Il. |
|
|
|
IL |
|
|
|
|
|
IN |
|
-- |
|
|
|
IA |
|
-- |
|
|
|
KS |
|
|
|
|
KY |
KY |
|
|
|
|
LA |
LA |
|
Me. |
Me. |
|
ME |
ME |
|
|
|
|
MD |
MD |
|
Ms. |
Mass. |
Mass. |
MASS |
MA |
|
Mic. T. |
|
|
|
MI |
|
-- |
|
|
|
MN |
|
Mi. |
Miss. |
Miss. |
MISS |
MS |
|
|
|
|
MO |
MO |
|
-- |
|
|
|
MT |
|
-- |
|
|
|
NB * *to NE in 1969 |
|
-- |
|
|
|
NV |
|
N. H. |
N. H. |
N. H. |
NH |
NH |
|
N. J. |
N. J. |
N. J. |
NJ |
NJ |
|
-- |
N. Mex. |
N. Mex. |
NM |
NM |
|
N. Y. |
N. Y. |
N. Y. |
NY |
NY |
|
N. C. |
N. C. |
N. C. |
NC |
NC |
|
-- |
-- |
N. Dak. |
ND |
ND |
|
O. |
|
|
|
OH |
|
-- |
-- |
|
|
OK |
|
-- |
Oreg. |
Oreg. |
|
OR |
|
|
|
|
PA |
PA |
|
-- |
-- |
P. R. |
PR |
PR |
|
R. I. |
R. I. |
R. I. |
RI |
RI |
|
S. C. |
S. C. |
S. C. |
SC |
SC |
|
-- |
-- |
S. Dak. |
SD |
SD |
|
Te. |
|
|
|
TN |
|
-- |
|
|
|
TX |
|
-- |
|
|
|
UT |
|
|
|
|
VT |
VT |
|
|
|
|
VA |
VA |
|
-- |
Wash. |
Wash. |
|
WA |
|
-- |
|
|
|
WV |
|
-- |
|
|
|
WI |
|
-- |
|
|
|
WY |
Sources: 1831, Table of Post Offices in
the
HISTORIAN
UNITED
STATES POSTAL SERVICE
DECEMBER
2011