ZIP code 60428: Markham, IL
ZIP code 60428 is in Markham, in Cook County, Illinois. It is in Illinois's 2nd congressional district (71%) and Illinois's 1st congressional district (29%). Its state senate district is State Senate District 15; its state house district is State House District 30.
See it on the mapAll of Illinois
City and county
| City or town | Share of ZIP residents |
|---|---|
| Markham | 100% |
| County | Share of ZIP residents |
|---|---|
| Cook County | 100% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| Bremen township | 73% |
| Thornton township | 27% |
Congressional districts
| Congressional district | Share of ZIP residents |
|---|---|
| Illinois's 2nd congressional district (IL-02) | 71% |
| Illinois's 1st congressional district (IL-01) | 29% |
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.
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 15 | 100% |
| State house district | Share of ZIP residents |
|---|---|
| State House District 30 | 100% |
Voting precincts
7 voting precincts overlap ZIP 60428. 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:60428")
ZIP 60428 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.