Boundary Atlas

ZIP code 21009: Bel Air South, MD

ZIP code 21009 is in Bel Air South (80% of residents) and Abingdon (15%), in Harford County, Maryland. 5.3% 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 7 (12%); its state house districts are State Legislative Subdistrict 34B (67%), State Legislative Subdistrict 34A (20%) and State Legislative Subdistrict 7B (12%).

31,835residents (2020 Census)
11.4 sq miland area
3cities and towns
1congressional district
9voting precincts

See it on the mapAll of Maryland

City and county

City or townShare of ZIP residents
Bel Air South80%
Abingdon15%
Edgewood0.2%

CountyShare of ZIP residents
Harford County100%

Town or county subdivisionShare of ZIP residents
District 1, Abingdon100%

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 7)J.B. Jennings (R)410-870-584812%
Delegate (State Legislative Subdistrict 34B)Susan McComas (R)67%
Delegate (State Legislative Subdistrict 34A)Andre Johnson (Democratic)20%
Delegate (State Legislative Subdistrict 34A)Steve Johnson (Democratic)20%
Delegate (State Legislative Subdistrict 7B)Lauren Arikan (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 712%

State house districtShare of ZIP residents
State Legislative Subdistrict 34B67%
State Legislative Subdistrict 34A20%
State Legislative Subdistrict 7B12%

Voting precincts

9 voting precincts overlap ZIP 21009. Map them, with each precinct's share of the ZIP's residents.

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ZIP 21009 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.