Texas was originally part of Mexico, achieving independence as the Republic of Texas in 1836. The United States acquired the area of Texas through annexation and Texas was admitted to the Union on March 1, 1845, as the 28^th state. At the time of statehood, Texas included part of present-day Colorado, Kansas, New Mexico, Oklahoma, and Wyoming. Texas sold territory to the United States in 1850 to assume generally the same boundary as the present state, but there were some subsequent revisions. In 1896, the Supreme Court ruled the Texas claim to the Greer County area in southwest Oklahoma to be invalid, and the area was officially deemed to be part of Oklahoma. An additional boundary dispute with Oklahoma was settled in 1930 by adding a narrow strip of territory to Texas. As the Rio Grande has changed its course, the United States and the Republic of Mexico have made periodic adjustments to their boundary that affected the boundary of Texas. 

Census data for Texas are available beginning with the 1850 census.

AMERICAN INDIAN AREAS

Texas has three federally recognized American Indian reservations, two with off-reservation trust land.

METROPOLITAN AND MICROPOLITAN STATISTICAL AREAS AND RELATED STATISTICAL AREAS

Texas has 25 metropolitan statistical areas, 44 micropolitan statistical areas, 2 metropolitan divisions, and 8 combined statistical areas.

COUNTIES

There are 254 counties in Texas.  All counties are functioning governmental units, each governed by a Commissioners Court.

COUNTY SUBDIVISIONS

There are 862 county subdivisions in Texas. They are all census county divisions (CCDs), which are delineated for statistical purposes, have no legal function, and are not governmental units.  CCDs were first established in Texas for the 1960 census.  Prior to 1960, the minor civil divisions used in the census included justice precincts and commissioner's precincts as well as beats, election precincts, voting precincts, and school districts.

PLACES

Texas has 1,752 places; 1,214 incorporated places and 538 census designated places (CDPs).  The incorporated places consist of 956 cities, 234 towns, and 24 villages.  Places in Texas have extensive annexation powers.  Nesbitt town and Rangerville village are inactive places in Texas.  A minimum population of 200 is required for incorporation.   

CENSUS TRACTS/BLOCK GROUPS/BLOCKS

Texas has 5,265 census tracts, 15,811 block groups, and 914,231 census blocks.

CONGRESSIONAL DISTRICTS

For the 111^th Congress (January 2009-January 2011), Texas has 32 congressional districts.  For the 113^th Congress (January 2013-January 2015), Texas will have 36 congressional districts as a result of reapportionment based on the 2010 Census.

SCHOOL DISTRICTS

There are 7 elementary school districts, 7 secondary school districts, and 1,022 unified school districts in Texas. 

STATE LEGISLATIVE DISTRICTS

There are 31 state senate districts and 150 state house districts in Texas.

URBAN AREAS

ZIP CODE TABULATION AREAS

There are 1,939 ZIP Code tabulation areas (ZCTAs) in Texas. 

OTHER INFORMATION OF GENERAL GEOGRAPHIC INTEREST

Data users should be aware of the large number of statistical and administrative areas in Texas.  Texas geographical files are large and complex.  The TIGER/Line Shapefiles for Texas are the largest of those for any state.

Texas is the only state to enter the United States by treaty as opposed to territorial annexation.  This allows the Texas flag to fly at the same height as the US flag.

¹  Source:  U.S. Department of Commerce, Bureau of the Census, Fourteenth Census of the United States, 1923
²  Source:  U.S. Census Bureau, recomputation for historical county level data which relied upon aggregate county level population data with an estimated county centroid resulting in a possible error of up to one mile.
³  Source:  U.S. Department of Commerce, Bureau of the Census, Centers of Population for States and Counties, 1974
⁴  Source:  U.S. Census Bureau, Geography Division, recomputation from archived national block group/enumeration area data resulting in a possible error of up to 1,000 feet.
⁵  Source:  U.S. Census Bureau, Geography Division, recomputation from archived national block group data resulting in a possible error of up to 1,000 feet.
⁶  Source:  U.S. Census Bureau, computation from national block-level data