Boundary Atlas

ZIP code 78661: Caldwell County, TX

ZIP code 78661 is in Caldwell County, Texas, outside any city or Census-designated place. It is in Texas's 27th congressional district. Its state senate district is State Senate District 21; its state house district is State House District 17.

304residents (2020 Census)
4.1 sq miland area
0cities and towns
1congressional district
1voting precincts

See it on the mapAll of Texas

City and county

Outside any city or Census-designated place.


CountyShare of ZIP residents
Caldwell County100%

Town or county subdivisionShare of ZIP residents
Martindale CCD72%
Luling CCD28%

Congressional district

Congressional districtShare of ZIP residents
Texas's 27th congressional district (TX-27)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (TX-27)Michael Cloud (R)202-225-7742100%
U.S. SenatorJohn Cornyn (R)202-224-2934 · contact formstatewide
U.S. SenatorTed Cruz (R)202-224-5922 · contact formstatewide
State Senator (State Senate District 21)Judith Zaffirini (Democratic)956-722-2293100%
State Representative (State House District 17)Stan Gerdes (R)512-321-3720100%

Elected in 2024 under TX's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).

Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 21100%

State house districtShare of ZIP residents
State House District 17100%

Voting precincts

1 voting precinct overlap ZIP 78661. Map them, with each precinct's share of the ZIP's residents.

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ZIP 78661 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.