Collin County is part of the Dallas/Fort Worth Metroplex. A small portion of the city of Dallas is located in the county. Other important cities in the county include Allen, Frisco, McKinney, Plano, Richardson, and Wylie.
Collin County is the richest county in Texas and the 23rd wealthiest county in the country.
As of the census of 2000, there were 491,675 people, 181,970 households, and 132,292 families residing in the county. The population density was 580 people per square mile (224/km²). There were 194,892 housing units at an average density of 230 per square mile (89/km²). The racial makeup of the county was 81.39% White, 4.79% Black or African American, 0.47% Native American, 6.92% Asian, 0.05% Pacific Islander, 4.26% from other races, and 2.11% from two or more races. 10.27% of the population were Hispanic or Latino of any race.
According to U.S. Census figures released in 2005, Collin County's demographics had changed significantly from just five years prior. The updated racial makeup figures for the county are as follows: 69% White, 6.7% African American, 9.5% Asian, and 12.8% Hispanic.
There were 181,970 households out of which 40.60% had children under the age of 18 living with them, 62.10% were married couples living together, 7.50% had a female householder with no husband present, and 27.30% were non-families. 22.10% of all households were made up of individuals and 3.10% had someone living alone who was 65 years of age or older. The average household size was 2.68 and the average family size was 3.18.
In the county, the population was spread out with 28.70% under the age of 18, 7.40% from 18 to 24, 37.90% from 25 to 44, 20.70% from 45 to 64, and 5.30% who were 65 years of age or older. The median age was 33 years. For every 100 females there were 99.80 males. For every 100 females age 18 and over, there were 97.80 males.
The median income for a household in the county was $70,835, and the median income for a family was $81,856. Males had a median income of $57,392 versus $36,604 for females. The per capita income for the county was $33,345. About 3.30% of families and 4.90% of the population were below the poverty line, including 5.10% of those under age 18 and 7.10% of those age 65 or over. Based on per capita income, Collin County is the richest county in Texas, and one of the wealthiest in the United States.
|2004||71.2% 174,435||28.1% 68,935||0.7% 1,784|
|2000||73.1% 128,179||24.4% 42,884||2.7% 4,357|
|1996||63.0% 83,750||28.5% 37,854||8.5% 11,321|
|1992||47.0% 60,514||19.0% 24,508||34.0% 43,811|
|1988||74.3% 67,776||25.1% 22,934||0.6% 520|
|1984||81.6% 61,095||18.2% 13,604||0.2% 139|
|1980||67.9% 36,559||28.2% 15,187||3.9% 2,115|
|1976||60.0% 21,608||39.0% 14,039||1.0% 353|
|1972||78.0% 17,667||21.1% 4,783||0.8% 187|
|1968||39.9% 6,494||36.4% 5,918||23.7% 3,850|
|1964||29.8% 3,341||70.0% 7,833||0.2% 19|
|1960||42.2% 3,865||57.1% 5,229||0.7% 64|
Collin County is a Republican-stronghold in Presidential and congressional elections. The last Democrat to win in the county was Lyndon Johnson in 1964. As the northern Dallas suburbs spilled into Collin County in the late 1960s and early 1970s its politics immediately swung to the Republican Party.
In the House of Representatives, the southwestern part of Collin County is represented in Texas's 3rd congressional district and the rest of the county is represented in the Texas's 4th congressional district. Both districts are held by Republicans, the 3rd by Sam Johnson, and the 4th by Ralph Hall, who only recently switched to the Republican Party.