Ellicott City is an unincorporated community and census-designated place in, and the county seat of, Howard County, Maryland, United States. Part of the Baltimore metropolitan area, its population was 65,834 at the 2010 census, qualifying it as the largest unincorporated county seat in the country.
Ellicott City is in northeastern Howard County, bordered to the east and north by the Patapsco River, which forms the Baltimore County line. The Ellicott City census-designated place (CDP) extends to the northwest beyond Marriottsville Road and to the southwest beyond Centennial Road. It is bordered to the south by Columbia at Maryland Route 108 and to the southeast by Ilchester at Maryland Route 104 and Bonnie Branch Road. According to the United States Census Bureau, the CDP has a total area of 30.1 square miles (77.9 km), of which 30.0 square miles (77.6 km) are land and 0.1 square miles (0.3 km), or 0.41%, are water.
Ellicott City is claimed to be built on seven hills. These hills lie southeast of the Historic District, which is in the Tiber River valley immediately west of the Patapsco River. The Tiber River is a small tributary of the Patapsco that forms the narrow valley followed by Main Street. Several deep stream valleys converge at this location, which increases the risk of flooding, but at the same time creates the town’s heights.
The heart of the Historic District is Main Street, where the oldest structures of the town stand. Smaller neighborhoods within the district include Tongue Row adjacent to Old Columbia Pike, and the West End, at the western end of Main Street.
As of the census of 2010, there were 65,834 people, 23,734 households, and 18,150 families residing in the CDP. The population density was 2,188.8 people per square mile (845.1/km²). There were 24,672 housing units at an average density of 822.4 per square mile (317.9/km²). The racial makeup of the CDP was 64.5% White, 22.9% Asian, 8.5% African American, 0.2% Native American, 0.0% Pacific Islander, 1.1% some other race, and 2.8% from two or more races. Hispanic or Latino of any race were 3.5% of the population.
There were 23,734 households, out of which 39.1% had children under the age of 18 living with them, 65.2% were headed by married couples living together, 8.2% had a female householder with no husband present, and 23.5% were non-families. 19.7% of all households were made up of individuals, and 8.4% had someone living alone who was 65 years of age or older. The average household size was 2.76, and the average family size was 3.20.
In the CDP, the population was distributed by age with 26.5% under the age of 18, 6.5% from 18 to 24, 24.0% from 25 to 44, 30.9% from 45 to 64, and 12.1% who were 65 years of age or older. The median age was 40.7 years. For every 100 females, there were 95.0 males. For every 100 females age 18 and over, there were 91.5 males.
According to a 2007 estimate, the median income for a household in the CDP was $103,464, and the median income for a family was $120,064. Males had a median income of $63,938 versus $41,721 for females. The per capita income for the CDP was $29,287. About 2.2% of families and 3.3% of the population were below the poverty line, including 3.3% of those under age 18 and 4.9% of those age 65 or over.
As of the census of 2000, there are 56,397 people, 20,250 households, and 15,288 families residing in the town. The population density is 679.8/km² (1,760.9/mi²). There are 20,789 housing units at an average density of 250.6/km² (649.1/mi²). The racial makeup of the town is 78.33% White, 7.34% African American, 0.15% Native American, 11.90% Asian, 0.02% Pacific Islander, 0.55% from other races, and 1.71% from two or more races. 2.14% of the population are Hispanic or Latino of any race.
There are 20,250 households out of which 41.2% have children under the age of 18 living with them, 65.3% are married couples living together, 7.6% have a female householder with no husband present, and 24.5% are non-families. 19.6% of all households are made up of individuals and 5.7% have someone living alone who is 65 years of age or older. The average household size is 2.76 and the average family size is 3.22.
In the town the population is spread out with 28.5% under the age of 18, 6.0% from 18 to 24, 30.8% from 25 to 44, 25.2% from 45 to 64, and 9.6% who are 65 years of age or older. The median age is 37 years. For every 100 females, there are 95.9 males. For every 100 females age 18 and over, there are 91.9 males.
The median income for a household in the town is $79,031, and the median income for a family is $91,968. Males have a median income of $63,938 versus $41,721 for females. The per capita income for the town is $33,316. 3.3% of the population and 2.2% of families are below the poverty line. Out of the total people living in poverty, 3.3% are under the age of 18 and 4.9% are 65 or older.