Boundary Atlas

ZIP code 78536: Delmita, TX

ZIP code 78536 is in Delmita (38% of residents) and San Isidro (38%), in Starr County, Texas. 24% of its residents live outside city limits. It is in Texas's 28th congressional district. Its state senate district is State Senate District 21; its state house district is State House District 31.

322residents (2020 Census)
43.7 sq miland area
2cities and towns
1congressional district
1voting precincts

See it on the mapAll of Texas

City and county

City or townShare of ZIP residents
Delmita38%
San Isidro38%

CountyShare of ZIP residents
Starr County100%

Town or county subdivisionShare of ZIP residents
Rio Grande City CCD100%

Congressional district

Congressional districtShare of ZIP residents
Texas's 28th congressional district (TX-28)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (TX-28)Henry Cuellar (D)202-225-1640100%
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 31)Ryan Guillen (R)100%

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 31100%

Voting precincts

1 voting precinct overlap ZIP 78536. Map them, with each precinct's share of the ZIP's residents.

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ZIP 78536 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.