Ohio's 1st congressional district (OH-01)
Ohio's 1st congressional district (OH-01) covers parts or all of Clinton County, Warren County and Hamilton County, and 81 ZIP codes (41 wholly inside it). Its 2020 population was 786,630. This is the map in force for the November 3, 2026 election.
Who represents OH-01
| Office | Member | Contact |
|---|---|---|
| U.S. Representative (OH-01) | Greg Landsman (D) | 202-225-2216 |
| U.S. Senator | Bernie Moreno (R) | 202-224-2315 |
| U.S. Senator | Jon Husted (R) | 202-224-3353 |
Elected in 2024 under OH's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).
Officials serving now (members of Congress until January 3, 2027). Sources: Members of Congress: the @unitedstates project, congress-legislators (CC0).
Counties
| County | Share of the county's residents in OH-01 |
|---|---|
| Clinton County | 100% |
| Warren County | 100% |
| Hamilton County | 60% |
ZIP codes
Percentages mark ZIPs only partly in OH-01: the share of that ZIP's residents inside it.
- 45001
- 45002 (98%)
- 45005 (99%)
- 45013 (<0.1%)
- 45030
- 45032
- 45033
- 45034
- 45036
- 45039
- 45040
- 45041
- 45042 (1.9%)
- 45044 (4.4%)
- 45050 (<0.1%)
- 45051
- 45052
- 45054
- 45065
- 45066 (95%)
- 45068 (98%)
- 45107 (84%)
- 45111
- 45113
- 45122 (5.5%)
- 45135 (2.9%)
- 45140 (48%)
- 45142 (9.2%)
- 45146
- 45148 (95%)
- 45150 (<0.1%)
- 45152
- 45159 (63%)
- 45162 (63%)
- 45164
- 45166
- 45169 (92%)
- 45174
- 45177
- 45202
- 45203
- 45204
- 45205
- 45206
- 45207
- 45208
- 45209
- 45211 (60%)
- 45212
- 45213 (82%)
- 45214
- 45215 (7.7%)
- 45216 (92%)
- 45217
- 45219
- 45220
- 45223
- 45224 (72%)
- 45225
- 45226
- 45227 (53%)
- 45229
- 45230
- 45231 (0.4%)
- 45232
- 45233 (95%)
- 45237 (67%)
- 45238 (91%)
- 45239 (23%)
- 45241 (0.4%)
- 45242 (11%)
- 45243 (28%)
- 45244 (55%)
- 45248 (37%)
- 45249 (55%)
- 45255 (70%)
- 45267
- 45327 (0.3%)
- 45335 (1.7%)
- 45342 (0.4%)
- 45458 (11%)
Towns
Adams township, Anderson township, Chester township, Clark township, Clear Creek township, Crosby township, Deerfield township, Delhi township, Elmwood Place village, Franklin township, Green township, Hamilton township, Harlan township, Harrison township, Jefferson township, Lebanon city, Liberty township, Loveland city, Loveland city, Marion township, Mason city, Massie township, Miami township, Milford city, Newtown village, Norwood city, Richland township, Salem township, St. Bernard village, Symmes township, Terrace Park village, Turtlecreek township, Union township, Union township, Vernon township, Washington township, Washington township, Wayne township, Wayne township and Whitewater township and others.
Get this in your AI agent
Your agent can draw every precinct in OH-01, or list them with population shares (related_geographies). Add https://boundarymcp.com/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
get_boundaries(id="us:congressional_district:3901", children_level="precinct", include_districts=True)