Boundary Atlas

ZIP code 78521: Brownsville, TX

ZIP code 78521 is in Brownsville (86% of residents) and South Point (1.1%), in Cameron County, Texas. 13% of its residents live outside city limits. It is in Texas's 34th congressional district. Its state senate district is State Senate District 27; its state house districts are State House District 38 (93%) and State House District 37 (6.9%).

88,708residents (2020 Census)
93.7 sq miland area
4cities and towns
1congressional district
21voting precincts

See it on the mapAll of Texas

City and county

City or townShare of ZIP residents
Brownsville86%
South Point1.1%
Reid Hope King0.8%
Villa Pancho0.5%

CountyShare of ZIP residents
Cameron County100%

Town or county subdivisionShare of ZIP residents
Brownsville CCD99%
East Cameron CCD1.3%

Congressional district

Congressional districtShare of ZIP residents
Texas's 34th congressional district (TX-34)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (TX-34)Vicente Gonzalez (D)202-225-2531100%
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 27)Adam Hinojosa (R)956-542-2211100%
State Representative (State House District 38)Erin Gámez (Democratic)93%
State Representative (State House District 37)Janie Lopez (R)956-247-36106.9%

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 27100%

State house districtShare of ZIP residents
State House District 3893%
State House District 376.9%

Voting precincts

21 voting precincts overlap ZIP 78521. Map them, with each precinct's share of the ZIP's residents.

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ZIP 78521 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.