Wabash County is a county located in the U.S. state of Illinois. According to the 2020 census, it had a population of 11,361. Its county seat is Mount Carmel. It is located in the southern portion of Illinois known locally as "Little Egypt".

Wabash County was formed in 1824 out of Edwards County. This averted to an armed confrontation between the militias of Albion and Mt. Carmel after the county seat was moved from a town near the current city of Mount Carmel to Albion.

The county is named for the Wabash River, which forms its eastern and southern borders. The name "Wabash" is an English spelling of the French name for the river, "Ouabache."' French traders named the river after the Miami Indian word for the river, "Wabashike," (pronounced "Wah-bah-she-keh"), the word for "pure white." Much of the river bottom is white limestone, now obscured by mud.

• 
  Wabash County at the time of its creation in 1824

A 329 acres (1.33 km) remnant of the county's original Eastern Woodlands ecosystem can be found in the Forest of the Wabash, located within the county's Beall Woods State Park.

In the 1920s a notable hotel and resort operated in Wabash County nearby the Grand Rapids Dam on the Wabash River. Named the Grand Rapids Hotel, it was owned by Frederick Hinde Zimmerman. During the hotel's nine-year existence, it catered to individuals from all over the United States. In July 2011, John Matthew Nolan published a detailed history of the Grand Rapids Hotel.

On the morning of April 18, 2008, at 4:37am local time, one of the largest earthquakes in Illinois history hit the area. The epicenter of this tremor was in Lick Prairie Township, near the middle of the county. The tremor was felt for a wide radius, more than 400 miles away in Nebraska.

According to the U.S. Census Bureau, the county has a total area of 228 square miles (590 km), of which 223 square miles (580 km) is land and 4.3 square miles (11 km) (1.9%) is water. It is the fifth-smallest county in Illinois by area.

The Wabash River to the east and the Bonpas Creek to the west join at the southern tip of the county; the Bonpas Creek separating the two counties, Wabash County from the Edwards County.

Mount Carmel, Illinois
Climate chart (explanation)
J F M A M J J A S O N D     2.9     38 21     2.7     44 25     4.2     54 35     4.2     66 44     5.1     76 54     3.7     85 63     4.2     89 67     3.6     87 65     2.8     81 57     3     70 45     4.2     55 36     3.1     43 25 █ Average max. and min. temperatures in °F █ Precipitation totals in inches Source: The Weather Channel
Metric conversion J F M A M J J A S O N D     74     3 −6     69     7 −4     105     12 2     108     19 7     130     24 12     94     29 17     108     32 19     92     31 18     71     27 14     77     21 7     106     13 2     77     6 −4 █ Average max. and min. temperatures in °C █ Precipitation totals in mm

In recent years, average temperatures in the county seat of Mount Carmel have ranged from a low of 21 °F (−6 °C) in January to a high of 89 °F (32 °C) in July, although a record low of −19 °F (−28 °C) was recorded in January 1985 and a record high of 102 °F (39 °C) was recorded in July 1988. Average monthly precipitation ranged from 2.73 inches (69 mm) in February to 5.12 inches (130 mm) in May.

• Rides Mass Transit District

• Illinois Route 1
• Illinois Route 15

• Lawrence County - north
• Knox County, Indiana - northeast
• Gibson County, Indiana - south and mostly east
• Edwards County - west
• Richland County - northwest

Historical population

Census	Pop.	Note	%±
1830	2,710		—
1840	4,240		56.5%
1850	4,690		10.6%
1860	7,313		55.9%
1870	8,841		20.9%
1880	9,945		12.5%
1890	11,866		19.3%
1900	12,583		6.0%
1910	14,913		18.5%
1920	14,034		−5.9%
1930	13,197		−6.0%
1940	13,724		4.0%
1950	14,651		6.8%
1960	14,047		−4.1%
1970	12,841		−8.6%
1980	13,713		6.8%
1990	13,111		−4.4%
2000	12,937		−1.3%
2010	11,947		−7.7%
2020	11,361		−4.9%
2023 (est.)	10,942		−3.7%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010-2013

As of the 2010 United States census, there were 11,947 people, 5,012 households, and 3,310 families residing in the county. The population density was 53.5 inhabitants per square mile (20.7/km). There were 5,585 housing units at an average density of 25.0 per square mile (9.7/km). The racial makeup of the county was 96.9% white, 0.6% black or African American, 0.6% Asian, 0.2% American Indian, 0.5% from other races, and 1.1% from two or more races. Those of Hispanic or Latino origin made up 1.3% of the population. In terms of ancestry, 25.6% were German, 12.3% were English, 11.7% were American, and 8.4% were Irish.

Of the 5,012 households, 29.0% had children under the age of 18 living with them, 52.9% were married couples living together, 9.3% had a female householder with no husband present, 34.0% were non-families, and 29.4% of all households were made up of individuals. The average household size was 2.37 and the average family size was 2.91. The median age was 42.0 years.

The median income for a household in the county was $46,026 and the median income for a family was $55,611. Males had a median income of $44,932 versus $28,292 for females. The per capita income for the county was $23,350. About 7.2% of families and 13.0% of the population were below the poverty line, including 12.2% of those under age 18 and 8.6% of those age 65 or over.

• Mount Carmel (seat)

• Allendale
• Bellmont
• Keensburg

• Adams Corner
• Cowling
• Friendsville
• Lancaster
• Maud
• Odgen
• Rochester

Wabash County is one of 17 Illinois counties that use the term precinct instead of township.

• Bellmont (Bellmont)
• Coffee (Keensburg)
• Compton (East Grayville)
• Friendsville (Friendsville)
• Lancaster (Lancaster)
• Lick Prairie (Lick Prairie)
• Mount Carmel (Mount Carmel)
• Wabash (Allendale)

Wabash County precincts and their boundaries

United States presidential election results for Wabash County, Illinois

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	4,095	76.16%	1,200	22.32%	82	1.53%
2020	4,237	75.57%	1,253	22.35%	117	2.09%
2016	4,047	74.07%	1,151	21.07%	266	4.87%
2012	3,478	67.74%	1,590	30.97%	66	1.29%
2008	3,254	56.16%	2,462	42.49%	78	1.35%
2004	4,212	70.13%	1,752	29.17%	42	0.70%
2000	3,406	61.84%	1,987	36.07%	115	2.09%
1996	2,381	45.15%	2,177	41.28%	716	13.58%
1992	2,485	39.82%	2,436	39.04%	1,319	21.14%
1988	3,453	60.30%	2,241	39.14%	32	0.56%
1984	3,639	66.73%	1,795	32.92%	19	0.35%
1980	3,571	61.18%	1,975	33.84%	291	4.99%
1976	3,388	54.41%	2,781	44.66%	58	0.93%
1972	4,310	68.35%	1,985	31.48%	11	0.17%
1968	3,529	55.21%	2,244	35.11%	619	9.68%
1964	2,905	43.84%	3,721	56.16%	0	0.00%
1960	4,261	58.55%	3,013	41.40%	4	0.05%
1956	4,425	61.92%	2,713	37.97%	8	0.11%
1952	4,246	61.38%	2,661	38.47%	10	0.14%
1948	2,916	49.44%	2,857	48.44%	125	2.12%
1944	3,496	52.95%	3,026	45.83%	81	1.23%
1940	3,659	45.94%	4,187	52.57%	119	1.49%
1936	2,860	39.59%	4,214	58.33%	150	2.08%
1932	2,309	34.49%	4,280	63.93%	106	1.58%
1928	2,373	37.26%	3,955	62.10%	41	0.64%
1924	2,564	45.61%	2,442	43.44%	615	10.94%
1920	2,871	52.40%	2,514	45.88%	94	1.72%
1916	2,600	42.41%	3,264	53.24%	267	4.35%
1912	601	18.08%	1,676	50.41%	1,048	31.52%
1908	1,511	43.06%	1,814	51.70%	184	5.24%
1904	1,298	44.57%	1,300	44.64%	314	10.78%
1900	1,226	40.96%	1,643	54.89%	124	4.14%
1896	1,321	42.22%	1,739	55.58%	69	2.21%
1892	1,112	40.69%	1,428	52.25%	193	7.06%

School districts include:

• Allendale Community Consolidated School District 17
• Edwards County Community Unit School District 1
• Grayville Community Unit School District 1
• Wabash Community Unit School District 348

• National Register of Historic Places listings in Wabash County
• Grand Rapids Hotel
• Grand Rapids Dam
• Hanging Rock (Wabash River)
• Charles T. Hinde
• Thomas S. Hinde
• Frederick Hinde Zimmerman