Boundary Atlas

ZIP code 18040: Chestnut Hill, PA

ZIP code 18040 is in Chestnut Hill (39% of residents) and Stockertown (1.4%), in Northampton County, Pennsylvania. 59% of its residents live outside city limits. It is in Pennsylvania's 7th congressional district. Its state senate district is State Senate District 18; its state house districts are State House District 138 (100%) and State House District 137 (0.3%).

16,980residents (2020 Census)
17.3 sq miland area
4cities and towns
1congressional district
13voting precincts

See it on the mapAll of Pennsylvania

City and county

City or townShare of ZIP residents
Chestnut Hill39%
Stockertown1.4%
Belfast0.2%
Martins Creek<0.1%

CountyShare of ZIP residents
Northampton County100%

Town or county subdivisionShare of ZIP residents
Forks township94%
Plainfield township2.3%
Lower Mount Bethel township1.5%
Stockertown borough1.4%
Palmer township0.3%

Congressional district

Congressional districtShare of ZIP residents
Pennsylvania's 7th congressional district (PA-07)100%

Elected officials

OfficeMemberContactShare of residents
U.S. Representative (PA-07)Ryan Mackenzie (R)202-225-6411100%
U.S. SenatorDavid McCormick (R)202-224-6324 · contact formstatewide
U.S. SenatorJohn Fetterman (D)202-224-4254 · contact formstatewide
State Senator (State Senate District 18)Lisa Boscola (Democratic)610-250-5627100%
State Representative (State House District 138)Ann Flood (R)610-746-2100100%
State Representative (State House District 137)Joe Emrick (R)484-544-01460.3%

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 18100%

State house districtShare of ZIP residents
State House District 138100%
State House District 1370.3%

Voting precincts

13 voting precincts overlap ZIP 18040. 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:18040")

ZIP 18040 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.