ZIP code 21771: Mount Airy, MD
ZIP code 21771 is in Mount Airy (31% of residents) and Green Valley (14%), in Frederick County (45%), Carroll County (43%), Howard County (10%) and Montgomery County (1.2%), Maryland. 54% of its residents live outside city limits. It is in Maryland's 6th congressional district (46%), Maryland's 3rd congressional district (45%), Maryland's 2nd congressional district (8.4%) and Maryland's 8th congressional district (0.2%). Its state senate districts are State Senate District 5 (55%), State Senate District 4 (34%), State Senate District 9 (11%) and State Senate District 14 (0.3%); its state house districts are State Legislative District 5 (55%), State Legislative District 4 (34%), State Legislative Subdistrict 9A (11%) and State Legislative District 14 (0.3%).
See it on the mapAll of Maryland
City and county
| City or town | Share of ZIP residents |
|---|---|
| Mount Airy | 31% |
| Green Valley | 14% |
| County | Share of ZIP residents |
|---|---|
| Frederick County | 45% |
| Carroll County | 43% |
| Howard County | 10% |
| Montgomery County | 1.2% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| District 13, Mount Airy | 35% |
| District 18, Woodville | 31% |
| District 9, New Market | 11% |
| District 4, Lisbon | 10% |
| District 9, Franklin | 8.4% |
| District 19, Linganore | 2.8% |
| District 12 | 1.0% |
| District 8, Liberty | 0.7% |
| District 1 | 0.2% |
| District 14, Berrett | 0.1% |
Congressional districts
| Congressional district | Share of ZIP residents |
|---|---|
| Maryland's 6th congressional district (MD-06) | 46% |
| Maryland's 3rd congressional district (MD-03) | 45% |
| Maryland's 2nd congressional district (MD-02) | 8.4% |
| Maryland's 8th congressional district (MD-08) | 0.2% |
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
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (MD-06) | April McClain Delaney (D) | 202-225-2721 | 46% |
| U.S. Representative (MD-03) | Sarah Elfreth (D) | 202-225-4016 | 45% |
| U.S. Representative (MD-02) | Johnny Olszewski, Jr. (D) | 202-225-3061 | 8.4% |
| U.S. Representative (MD-08) | Jamie Raskin (D) | 202-225-5341 | 0.2% |
| U.S. Senator | Angela D. Alsobrooks (D) | 202-224-4524 · contact form | statewide |
| U.S. Senator | Chris Van Hollen (D) | 202-224-4654 · contact form | statewide |
Plus 15 state legislators across 8 districts. Look up an address for the exact ones.
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
- Mount Airy laws: search for the Mount Airy, Maryland code of ordinances
- Green Valley laws: search for the Green Valley, Maryland code of ordinances
- Frederick County website: http://FrederickCountyMD.gov/
- Frederick County laws: search for the Frederick County, Maryland code of ordinances
- Carroll County website: https://www.carrollcountymd.gov/
- Carroll County laws: search for the Carroll County, Maryland code of ordinances
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 5 | 55% |
| State Senate District 4 | 34% |
| State Senate District 9 | 11% |
| State Senate District 14 | 0.3% |
| State house district | Share of ZIP residents |
|---|---|
| State Legislative District 5 | 55% |
| State Legislative District 4 | 34% |
| State Legislative Subdistrict 9A | 11% |
| State Legislative District 14 | 0.3% |
Voting precincts
15 voting precincts overlap ZIP 21771. 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://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
related_geographies(id="us:zcta:21771")
ZIP 21771 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.