ZIP code 53538: Fort Atkinson, WI
ZIP code 53538 is in Fort Atkinson (68% of residents), Lake Koshkonong (5.2%) and Hebron (1.1%), in Jefferson County (99%) and Rock County (0.7%), Wisconsin. 26% of its residents live outside city limits. It is in Wisconsin's 5th congressional district (99%) and Wisconsin's 1st congressional district (0.7%). Its state senate districts are State Senate District 16 (95%), State Senate District 33 (3.3%), State Senate District 15 (0.8%) and State Senate District 13 (0.7%); its state house districts are Assembly District 46 (95%), Assembly District 97 (3.3%), Assembly District 43 (0.8%) and Assembly District 38 (0.7%).
See it on the mapAll of Wisconsin
City and county
| City or town | Share of ZIP residents |
|---|---|
| Fort Atkinson | 68% |
| Lake Koshkonong | 5.2% |
| Hebron | 1.1% |
| County | Share of ZIP residents |
|---|---|
| Jefferson County | 99% |
| Rock County | 0.7% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| Fort Atkinson city | 68% |
| Koshkonong town | 19% |
| Oakland town | 5.5% |
| Hebron town | 3.3% |
| Sumner town | 2.7% |
| Jefferson town | 1.4% |
| Milton town | 0.6% |
| Cold Spring town | 0.1% |
| Lima town | <0.1% |
Congressional districts
| Congressional district | Share of ZIP residents |
|---|---|
| Wisconsin's 5th congressional district (WI-05) | 99% |
| Wisconsin's 1st congressional district (WI-01) | 0.7% |
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 (WI-05) | Scott Fitzgerald (R) | 202-225-5101 | 99% |
| U.S. Representative (WI-01) | Bryan Steil (R) | 202-225-3031 | 0.7% |
| U.S. Senator | Ron Johnson (R) | 202-224-5323 · contact form | statewide |
| U.S. Senator | Tammy Baldwin (D) | 202-224-5653 · contact form | statewide |
| State Senator (State Senate District 16) | Melissa Ratcliff (Democratic) | 95% | |
| State Senator (State Senate District 33) | Chris Kapenga (R) | 3.3% | |
| State Senator (State Senate District 15) | Mark Spreitzer (Democratic) | 0.8% | |
| State Senator (State Senate District 13) | John Jagler (R) | 0.7% | |
| Assembly Member (Assembly District 46) | Joan Fitzgerald (Democratic) | 95% | |
| Assembly Member (Assembly District 97) | Cindi Duchow (R) | 3.3% | |
| Assembly Member (Assembly District 43) | Brienne Brown (Democratic) | 0.8% | |
| Assembly Member (Assembly District 38) | Will Penterman (R) | 0.7% |
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
- Fort Atkinson website: http://www.fortatkinsonwi.net
- Fort Atkinson laws: search for the Fort Atkinson, Wisconsin code of ordinances
- Lake Koshkonong laws: search for the Lake Koshkonong, Wisconsin code of ordinances
- Hebron laws: search for the Hebron, Wisconsin code of ordinances
- Jefferson County website: https://www.jeffersoncountywi.gov/
- Jefferson County laws: search for the Jefferson County, Wisconsin code of ordinances
- Rock County website: https://www.co.rock.wi.us/
- Rock County laws: search for the Rock County, Wisconsin code of ordinances
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 16 | 95% |
| State Senate District 33 | 3.3% |
| State Senate District 15 | 0.8% |
| State Senate District 13 | 0.7% |
| State house district | Share of ZIP residents |
|---|---|
| Assembly District 46 | 95% |
| Assembly District 97 | 3.3% |
| Assembly District 43 | 0.8% |
| Assembly District 38 | 0.7% |
Voting precincts
27 voting precincts overlap ZIP 53538. 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:53538")
ZIP 53538 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.