Boundary Atlas

ZIP code 78121: Wilson County, TX

ZIP code 78121 is in La Vernia (7.1% of residents) and New Berlin (1.1%), in Wilson County (91%) and Guadalupe County (8.6%), Texas. 92% of its residents live outside city limits. It is in Texas's 35th congressional district. Its state senate districts are State Senate District 21 (93%) and State Senate District 19 (6.9%); its state house districts are State House District 31 (91%) and State House District 44 (8.6%).

15,206residents (2020 Census)
102.6 sq miland area
2cities and towns
1congressional district
7voting precincts

See it on the mapAll of Texas

City and county

City or townShare of ZIP residents
La Vernia7.1%
New Berlin1.1%

CountyShare of ZIP residents
Wilson County91%
Guadalupe County8.6%

Town or county subdivisionShare of ZIP residents
La Vernia CCD68%
Floresville CCD23%
Southwest Guadalupe CCD8.6%

Congressional district

Congressional districtShare of ZIP residents
Texas's 35th congressional district (TX-35)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (TX-35)Greg Casar (D)202-225-5645100%
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)956-722-229393%
State Senator (State Senate District 19)Roland Gutierrez (Democratic)830-278-12346.9%
State Representative (State House District 31)Ryan Guillen (R)91%
State Representative (State House District 44)Alan Schoolcraft (R)8.6%

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 2193%
State Senate District 196.9%

State house districtShare of ZIP residents
State House District 3191%
State House District 448.6%

Voting precincts

7 voting precincts overlap ZIP 78121. Map them, with each precinct's share of the ZIP's residents.

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ZIP 78121 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.