Whiteside County is a county in Illinois, United States, on the east bank of the Mississippi River in the state’s north-west corner. It had a population of 55,691 people at the 2020 census and covers 697 square miles (1,810 km2), of which 684 square miles is land and 12 square miles is water, centred near 41°45′N 89°55′W.
Morrison is the county seat, and its postal code is 61270. The county has five cities, six villages, two census-designated places and several unincorporated communities, all in the Central time zone (UTC−6). The FIPS county code is 17195.
Towns & Villages in Whiteside County
Sterling is the largest city in the county; Morrison, on the eastern side of the county, is the seat of government. Ronald Reagan was born in Tampico in 1911, and the village still trades on that history.
| Place | Type | Township | Pop. | ZIP |
|---|---|---|---|---|
| Sterling | City | Sterling | 14,764 | 61081 |
| Rock Falls | City | Coloma | — | 61071 |
| Morrison | City · seat | Union Grove | — | 61270 |
| Fulton | City | Fulton | — | 61252 |
| Prophetstown | City | Prophetstown | — | 61277 |
| Albany | Village | Albany | 864 | 61230 |
| Coleta | Village | Montmorency | 167 | — |
| Deer Grove | Village | Hume | 38 | — |
| Erie | Village | Erie | — | 61250 |
| Lyndon | Village | Lyndon | — | 61261 |
| Tampico | Village | Tampico | — | 61283 |
| Como | CDP | Genesee | — | — |
| Galt | CDP | Hopkins | — | — |
| Agnew | Unincorp. | Newton | — | — |
| Fenton | Unincorp. | Fenton | — | 61251 |
| Hahnaman | Unincorp. | Hahnaman | — | — |
| Round Grove | Unincorp. | Jordan | — | — |
| Spring Hill | Unincorp. | Portland | — | — |
| Union Grove | Unincorp. | Union Grove | — | — |
| Unionville | Unincorp. | Clyde | — | — |
| Yeoward Addition | Unincorp. | Genesee | — | — |
Townships
| Township | Pop. (2020) | Main settlements |
|---|---|---|
| Albany | — | Albany |
| Clyde | — | Unionville |
| Coloma | — | Rock Falls |
| Erie | — | Erie |
| Fenton | — | Fenton |
| Fulton | — | Fulton |
| Garden Plain | — | rural farmland |
| Genesee | — | Como, Yeoward Addition |
| Hahnaman | — | Hahnaman |
| Hopkins | — | Galt |
| Hume | — | Deer Grove |
| Jordan | — | Round Grove |
| Lyndon | — | Lyndon |
| Montmorency | — | Coleta |
| Mount Pleasant | — | rural farmland |
| Newton | — | Agnew |
| Portland | — | Spring Hill |
| Prophetstown | — | Prophetstown |
| Sterling | — | Sterling |
| Tampico | — | Tampico |
| Union Grove | — | Morrison, Union Grove |
| Ustick | — | rural farmland |
ZIP Codes
- 61081 — Sterling (also serves surrounding Sterling Township)
- 61071 — Rock Falls
- 61270 — Morrison (county seat)
- 61252 — Fulton
- 61277 — Prophetstown
- 61230 — Albany
- 61250 — Erie
- 61261 — Lyndon
- 61283 — Tampico
- 61251 — Fenton
Coleta, Deer Grove, Como, Galt and the county’s smaller unincorporated places share a ZIP with the nearest post-office town rather than having their own.
Geography
Whiteside County sits on the east bank of the Mississippi River, which forms its entire western boundary with Clinton County, Iowa. The Rock River crosses the county from northeast to southwest through Sterling and Rock Falls before joining the Mississippi. The terrain is flat to gently rolling glacial till prairie, given over mostly to corn and soybean farmland outside the river towns.
The county borders:
- Carroll County to the north
- Ogle County to the northeast
- Lee County to the east
- Bureau County to the southeast
- Henry County to the south
- Rock Island County to the southwest
- Clinton County, Iowa, across the Mississippi to the west
Demographics
The 2020 census counted 55,691 residents, a decline from the county’s mid-20th-century peak. Sterling (14,764) and Rock Falls form the county’s twin-city core along the Rock River; together with Morrison and Fulton they hold most of the county’s population, while the surrounding townships remain sparsely settled farm country. Whiteside County’s median household income runs below the Illinois state figure of $80,306, reflecting the area’s manufacturing and agricultural base. Overall density works out to roughly 81 people per square mile of land.
Economy & Local Life
Agriculture — corn, soybeans and livestock — underpins the county’s rural townships, while Sterling and Rock Falls carry a manufacturing base built around metal fabrication and machine-shop work that grew up along the Rock River’s early industrial dam sites. Wahl Clipper, a longtime Sterling-based grooming-equipment maker, is among the area’s best-known employers. Morrison serves as the county’s government and courthouse hub. Tampico draws visitors year-round to the modest boyhood home of Ronald Reagan, the county’s best-known native son.
History
Whiteside County was organized in 1836 out of territory taken from Jo Daviess and Henry counties, and its boundaries have not changed since. It is named for General Samuel Whiteside, an officer in the War of 1812 and the Black Hawk War. The Rock River’s early water-power sites drew mills and, later, factories to Sterling and Rock Falls, while the flatter western townships developed as grain-farming country. Ronald Reagan’s birth in Tampico in 1911 remains the county’s most-cited historical event.
Getting There
Interstate 88 crosses the county through Sterling and Rock Falls, and U.S. Route 30 runs east–west through the northern part of the county. Whiteside County Airport (Joseph H. Bittorf Field, identifier SQI) at Rock Falls is a general-aviation field with no scheduled airline service.
- Sterling — 0 miles (county seat of the Rock River twin cities)
- Morrison — 18 miles west of Sterling
- Fulton — 24 miles west of Sterling, on the Mississippi
- Prophetstown — 15 miles southwest of Sterling
The nearest Amtrak service and the nearest major commercial airport are both across the Mississippi in the Quad Cities area, roughly 40 miles southwest.
Frequently Asked Questions
What is the Morrison postcode?
61270.
What is the population of Whiteside County?
55,691 people at the 2020 census.
What is the largest city in Whiteside County?
Sterling, with 14,764 residents at the 2020 census, across the Rock River from its twin city, Rock Falls.
Where was Ronald Reagan born?
In the village of Tampico, in Whiteside County, in 1911.
What river forms the county’s western border?
The Mississippi River, which separates Whiteside County from Clinton County, Iowa.
How many townships does Whiteside County have?
Twenty-two civil townships.
What interstate runs through Whiteside County?
Interstate 88, through Sterling and Rock Falls.
More counties in this state: Towns and villages in Illinois.