Grant County is a county located in the northern part of the U.S. commonwealth of Kentucky. As of the 2020 census, the population was 24,941. Its county seat is Williamstown. The county was formed in 1820 and named for Colonel John Grant, who led a party of settlers in 1779 to establish Grant's Station, in today's Bourbon County, Kentucky. Grant County is included in the Cincinnati-Middletown, OH-KY-IN Metropolitan Statistical Area. Grant County residents voted to allow full alcohol sales in the county by a margin of 56% to 44% in a special election on December 22, 2015. In the 19th century, Grant County had multiple saloons.

The Grant County News, established in 1906 and published in Williamstown, is preserved on microfilm by the University of Kentucky Libraries. The microfilm holdings are listed in a master negative database on the UK Libraries Preservation and Digital Programs website.

Grant County was established in 1820 from land taken from Pendleton County. The historic courthouse, built in 1939, replaced two earlier structures. A new judicial center was completed in April 2010. In 1975, many residents reported seeing a UFO at Williamstown Lake.

According to the United States Census Bureau, the county has a total area of 261 square miles (680 km), of which 258 square miles (670 km) is land and 2.8 square miles (7.3 km) (1.1%) is water.

• Boone County (north)
• Kenton County (northeast)
• Pendleton County (east)
• Harrison County (southeast)
• Scott County (south)
• Owen County (west)
• Gallatin County (northwest)

Historical population

Census	Pop.	Note	%±
1830	2,986		—
1840	4,192		40.4%
1850	6,531		55.8%
1860	8,356		27.9%
1870	9,529		14.0%
1880	13,083		37.3%
1890	12,671		−3.1%
1900	13,239		4.5%
1910	10,581		−20.1%
1920	10,435		−1.4%
1930	9,876		−5.4%
1940	9,876		0.0%
1950	9,809		−0.7%
1960	9,489		−3.3%
1970	9,999		5.4%
1980	13,308		33.1%
1990	15,737		18.3%
2000	22,384		42.2%
2010	24,682		10.3%
2020	24,941		1.0%
2023 (est.)	25,619		2.7%
U.S. Decennial Census 1790-1960 1900-1990 1990-2000 2010-2020

As of the census of 2000, there were 22,384 people, 8,175 households, and 6,221 families residing in the county. The population density was 86 per square mile (33/km). There were 9,306 housing units at an average density of 36 per square mile (14/km). The racial makeup of the county was 98.31% White, 0.25% Black or African American, 0.23% Native American, 0.29% Asian, 0.05% Pacific Islander, 0.32% from other races, and 0.54% from two or more races. 1.04% of the population were Hispanic or Latino of any race.

There were 8,175 households, out of which 39.60% had children under the age of 18 living with them, 60.10% were married couples living together, 11.10% had a female householder with no husband present, and 23.90% were non-families. 19.80% of all households were made up of individuals, and 8.20% had someone living alone who was 65 years of age or older. The average household size was 2.72 and the average family size was 3.10.

In the county, the population was spread out, with 28.70% under the age of 18, 9.40% from 18 to 24, 31.50% from 25 to 44, 20.90% from 45 to 64, and 9.50% who were 65 years of age or older. The median age was 33 years. For every 100 females there were 97.10 males. For every 100 females age 18 and over, there were 94.80 males.

The median income for a household in the county was $38,438, and the median income for a family was $42,605. Males had a median income of $31,987 versus $23,669 for females. The per capita income for the county was $16,776. About 9.00% of families and 11.10% of the population were below the poverty line, including 15.10% of those under age 18 and 13.40% of those age 65 or over.

Grant County has six schools: Crittenden Mt Zion (CMZ), Dry Ridge Elementary (DRE), Sherman Elementary (SES), Mason Corinth Elementary (MCE), Grant County Middle School (GCMS), Grant County High School (GCHS) and Williamstown Independent Schools (WES)- (WMS) – (WHS).

Grant County's only library is located in Williamstown.

United States presidential election results for Grant County, Kentucky

Year	Republican		Democratic		Third party(ies)
	No.	%	No.	%	No.	%
2024	9,372	81.72%	1,944	16.95%	153	1.33%
2020	8,725	78.55%	2,205	19.85%	178	1.60%
2016	7,268	76.03%	1,910	19.98%	381	3.99%
2012	5,664	65.80%	2,810	32.64%	134	1.56%
2008	5,510	62.94%	3,112	35.55%	132	1.51%
2004	5,951	67.44%	2,818	31.94%	55	0.62%
2000	4,405	62.02%	2,568	36.15%	130	1.83%
1996	2,697	45.43%	2,541	42.80%	699	11.77%
1992	2,128	39.44%	2,097	38.87%	1,170	21.69%
1988	2,835	59.05%	1,896	39.49%	70	1.46%
1984	2,840	61.70%	1,685	36.61%	78	1.69%
1980	1,779	42.53%	2,272	54.32%	132	3.16%
1976	1,212	33.35%	2,336	64.28%	86	2.37%
1972	2,086	64.03%	1,054	32.35%	118	3.62%
1968	1,386	39.35%	1,169	33.19%	967	27.46%
1964	1,068	30.13%	2,461	69.42%	16	0.45%
1960	2,163	53.25%	1,899	46.75%	0	0.00%
1956	1,680	42.04%	2,300	57.56%	16	0.40%
1952	1,609	38.67%	2,545	61.16%	7	0.17%
1948	1,154	30.22%	2,633	68.94%	32	0.84%
1944	1,621	40.05%	2,413	59.62%	13	0.32%
1940	1,535	35.96%	2,729	63.93%	5	0.12%
1936	1,353	34.35%	2,560	64.99%	26	0.66%
1932	1,407	30.64%	3,148	68.55%	37	0.81%
1928	2,448	59.48%	1,662	40.38%	6	0.15%
1924	1,404	39.45%	1,923	54.03%	232	6.52%
1920	1,613	37.19%	2,686	61.93%	38	0.88%
1916	1,078	36.44%	1,841	62.24%	39	1.32%
1912	837	32.43%	1,562	60.52%	182	7.05%

Public transportation is provided by Senior Services of Northern Kentucky with demand-response service.

Grant County, specifically in Williamstown, is the location of the Ark Encounter, operated by the Christian apologetics organization Answers in Genesis and opened in 2016.

• Corinth
• Crittenden
• Dry Ridge
• Williamstown (county seat)

• Jonesville

• National Register of Historic Places listings in Grant County, Kentucky

• Historical Texts and Images of Grant County

38°38′N 84°37′W / 38.64°N 84.61°W / 38.64; -84.61