Boundary Atlas

ZIP code 78257: San Antonio, TX

ZIP code 78257 is in San Antonio (95% of residents), in Bexar County, Texas. 5.3% of its residents live outside city limits. It is in Texas's 23rd congressional district (89%) and Texas's 21st congressional district (11%). Its state senate districts are State Senate District 25 (89%), State Senate District 26 (10%) and State Senate District 19 (0.3%); its state house districts are State House District 122 (89%) and State House District 116 (11%).

12,173residents (2020 Census)
28.5 sq miland area
1cities and towns
2congressional districts
9voting precincts

See it on the mapAll of Texas

City and county

City or townShare of ZIP residents
San Antonio95%

CountyShare of ZIP residents
Bexar County100%

Town or county subdivisionShare of ZIP residents
San Antonio North CCD96%
San Antonio Northwest CCD4.2%

Congressional districts

Congressional districtShare of ZIP residents
Texas's 23rd congressional district (TX-23)89%
Texas's 21st congressional district (TX-21)11%

This ZIP is split between districts. A mailing address in it could be in either; the map or locate_point gives the district for an exact address.

Elected officials

OfficeMemberContactShare of residents
MayorGina Ortiz Jones95%
U.S. Representative (TX-21)Chip Roy (R)202-225-423611%
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 25)Donna Campbell (R)830-626-006589%
State Senator (State Senate District 26)José Menéndez (Democratic)210-733-660410%
State Senator (State Senate District 19)Roland Gutierrez (Democratic)830-278-12340.3%
State Representative (State House District 122)Mark Dorazio (R)89%
State Representative (State House District 116)Trey Martinez Fischer (Democratic)210-733-839111%
U.S. Representative (TX-23)Vacant

From Wikidata (community-maintained); confirm on the city's website.

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); Mayors: Wikidata (CC0).

Local government

State legislative districts

State senate districtShare of ZIP residents
State Senate District 2589%
State Senate District 2610%
State Senate District 190.3%

State house districtShare of ZIP residents
State House District 12289%
State House District 11611%

Voting precincts

9 voting precincts overlap ZIP 78257. Map them, with each precinct's share of the ZIP's residents.

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related_geographies(id="us:zcta:78257")

ZIP 78257 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.