Boundary Atlas

ZIP code 20657: Chesapeake Ranch Estates, MD

ZIP code 20657 is in Chesapeake Ranch Estates (51% of residents), Drum Point (13%) and Lusby (10%), in Calvert County, Maryland. 25% of its residents live outside city limits. It is in Maryland's 5th congressional district. Its state senate districts are State Senate District 29 (95%) and State Senate District 27 (5.4%); its state house districts are State Legislative Subdistrict 29C (95%) and State Legislative Subdistrict 27C (5.4%).

20,042residents (2020 Census)
29.9 sq miland area
3cities and towns
1congressional district
4voting precincts

See it on the mapAll of Maryland

City and county

City or townShare of ZIP residents
Chesapeake Ranch Estates51%
Drum Point13%
Lusby10%

CountyShare of ZIP residents
Calvert County100%

Town or county subdivisionShare of ZIP residents
District 1, Solomons Island100%

Congressional district

Congressional districtShare of ZIP residents
Maryland's 5th congressional district (MD-05)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (MD-05)Steny H. Hoyer (D)202-225-4131100%
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 29)Jack Bailey (R)240-309-423895%
State Senator (State Senate District 27)Kevin Harris (Democratic)5.4%
Delegate (State Legislative Subdistrict 29C)Todd Morgan (R)95%
Delegate (State Legislative Subdistrict 27C)Mark Fisher (R)5.4%

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 2995%
State Senate District 275.4%

State house districtShare of ZIP residents
State Legislative Subdistrict 29C95%
State Legislative Subdistrict 27C5.4%

Voting precincts

4 voting precincts overlap ZIP 20657. Map them, with each precinct's share of the ZIP's residents.

Get this in your AI agent

Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:

related_geographies(id="us:zcta:20657")

ZIP 20657 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.