Boundary Atlas

ZIP code 21078: Havre de Grace, MD

ZIP code 21078 is in Havre de Grace (73% of residents) and Aberdeen (3.0%), in Harford County, Maryland. 24% of its residents live outside city limits. It is in Maryland's 1st congressional district. Its state senate districts are State Senate District 34 (88%) and State Senate District 35 (12%); its state house districts are State Legislative Subdistrict 34A (88%) and State Legislative Subdistrict 35A (12%).

20,321residents (2020 Census)
30.1 sq miland area
2cities and towns
1congressional district
8voting precincts

See it on the mapAll of Maryland

City and county

City or townShare of ZIP residents
Havre de Grace73%
Aberdeen3.0%

CountyShare of ZIP residents
Harford County100%

Town or county subdivisionShare of ZIP residents
District 6, Havre de Grace82%
District 2, Halls Cross Roads18%

Congressional district

Congressional districtShare of ZIP residents
Maryland's 1st congressional district (MD-01)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (MD-01)Andy Harris (R)202-225-5311100%
U.S. SenatorAngela D. Alsobrooks (D)202-224-4524 · contact formstatewide
U.S. SenatorChris Van Hollen (D)202-224-4654 · contact formstatewide
State Senator (State Senate District 34)Mary-Dulany James (Democratic)88%
State Senator (State Senate District 35)Jason Gallion (R)12%
Delegate (State Legislative Subdistrict 34A)Andre Johnson (Democratic)88%
Delegate (State Legislative Subdistrict 34A)Steve Johnson (Democratic)88%
Delegate (State Legislative Subdistrict 35A)Mike Griffith (R)12%
Delegate (State Legislative Subdistrict 35A)Teresa Reilly (R)12%

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 3488%
State Senate District 3512%

State house districtShare of ZIP residents
State Legislative Subdistrict 34A88%
State Legislative Subdistrict 35A12%

Voting precincts

8 voting precincts overlap ZIP 21078. Map them, with each precinct's share of the ZIP's residents.

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ZIP 21078 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.