Dallas County, Iowa

Dallas County is a county located in the U.S. state of Iowa. As of the 2020 census, its population was 99,678,^[2] and was estimated to be 115,343 in 2024.^[3] making it the sixth-most populous county in Iowa. Between 2010 and 2020, it was the fastest growing county in Iowa and one of the fastest growing in the country. The county seat is Adel and the largest city is Waukee.^[4] The county was named for George M. Dallas, Vice President of the United States under James K. Polk, the namesake of neighboring Polk County.

Dallas County is included in the Des Moines–West Des Moines, IA Metropolitan Statistical Area.^[5]

The land that now forms Dallas County was ceded by the Sac and Fox nation to the United States in a treaty signed on October 11, 1842. White settlement in Dallas County began afterwards, many of the settlers were of Yankee descent.

On January 13, 1846, the legislative body of the Iowa Territory authorized the creation of twelve counties in the Iowa Territory,^[6] with general descriptions of their boundaries.^[7] Dallas County's name referred to United States Vice President George M. Dallas, who served from 1845 to 1849.

In 1847 the county residents voted to designate Penoch as the county seat (the name was changed to Adel in 1849). The county's population grew rapidly, with settlers coming to claim homesteads. By 1870, the population had crossed the 12,000 mark.

According to the United States Census Bureau, the county has a total area of 591.605 square miles (1,532.25 km²), of which 588.230 square miles (1,523.51 km²) is land and 3.375 square miles (8.74 km²) (0.57%) is water.^[8] It is the 24th largest county in Iowa by total area.^[9]

• Interstate 80 – runs east-northeast across the southern portion of the county, passing Dexter and De Soto on its way to Des Moines
• U.S. Highway 6 – from its starting point in Adel, runs east across the midsection of the county on its way to Des Moines
• U.S. Highway 169 – runs north–south through the center of the county, from Bouton to Adel to De Soto
• Iowa Highway 17 – from its starting point (intersection with Iowa 141) at Granger, runs north along the county's eastern boundary, into Boone County
• Iowa Highway 44 – runs east–west through the center of the county, through Dallas Center
• Iowa Highway 141 – runs east across northern portion of county, through Dawson, Perry, Bouton and Woodward, then southeast to exit into Polk County at Granger
• Iowa Highway 144 - from its starting point (intersection w Iowa 141) at Perry, runs north into Boone County
• Iowa Highway 210 – from its starting point (intersection w Iowa 141), runs north to Woodward and continues into Boone County^[10]

• Adair County – southwest
• Boone County – north
• Greene County – north and northwest
• Guthrie County – west
• Madison County – south
• Polk County – east
• Warren County – southeast

As of the second quarter of 2025, the median home value in Dallas County was $379,620.^[16]

As of the 2024 American Community Survey, there are 46,373 estimated households in Dallas County with an average of 2.47 persons per household. The county has a median household income of $95,334. Approximately 5.7% of the county's population lives at or below the poverty line. Dallas County has an estimated 73.4% employment rate, with 54.1% of the population holding a bachelor's degree or higher and 94.4% holding a high school diploma.^[3] There were 48,279 housing units at an average density of 82.08 per square mile (31.7/km²).

The top five reported languages (people were allowed to report up to two languages, thus the figures will generally add to more than 100%) were English (86.0%), Spanish (4.3%), Indo-European (3.2%), Asian and Pacific Islander (3.8%), and Other (2.7%).

The median age in the county was 36.6 years.

As of the 2020 census, there were 99,678 people, 38,291 households, and 26,000 families residing in the county. The population density was 169.45 inhabitants per square mile (65.4/km²). There were 41,125 housing units at an average density of 69.91 per square mile (27.0/km²).^[22]

The median age was 35.4 years. 27.7% of residents were under the age of 18 and 12.5% of residents were 65 years of age or older. For every 100 females there were 96.7 males, and for every 100 females age 18 and over there were 94.0 males age 18 and over.^[22]

The racial makeup of the county was 83.6% White, 2.7% Black or African American, 0.2% American Indian and Alaska Native, 5.0% Asian, <0.1% Native Hawaiian and Pacific Islander, 2.6% from some other race, and 5.8% from two or more races. Hispanic or Latino residents of any race comprised 6.5% of the population.^[23]

78.7% of residents lived in urban areas, while 21.3% lived in rural areas.^[24]

There were 38,291 households in the county, of which 37.2% had children under the age of 18 living in them. Of all households, 55.8% were married-couple households, 15.2% were households with a male householder and no spouse or partner present, and 22.1% were households with a female householder and no spouse or partner present. About 25.2% of all households were made up of individuals and 8.4% had someone living alone who was 65 years of age or older.^[22]

Of the 41,125 housing units, 6.9% were vacant. Among occupied housing units, 70.4% were owner-occupied and 29.6% were renter-occupied. The homeowner vacancy rate was 2.2% and the rental vacancy rate was 10.1%.^[22]

As of the 2010 census, there were 66,135 people, 25,239 households, and _ families residing in the county. The population density was 112.43 inhabitants per square mile (43.4/km²). There were 27,259 housing units at an average density of 46.34 per square mile (17.9/km²). The racial makeup of the county was 92.19% White, 1.39% African American, 0.19% Native American, 2.51% Asian, 0.06% Pacific Islander, 2.13% from some other races and 1.53% from two or more races. Hispanic or Latino people of any race were 6.14% of the population.

As of the 2000 census, there were 40,750 people, 15,584 households, and 11,173 families residing in the county. The population density was 69.28 inhabitants per square mile (26.7/km²). There were 16,529 housing units at an average density of 28.10 per square mile (10.8/km²). The racial makeup of the county was 94.75% White, 0.74% African American, 0.15% Native American, 0.69% Asian, 0.04% Pacific Islander, 2.79% from some other races and 0.84% from two or more races. Hispanic or Latino people of any race were 5.40% of the population.

There were 15,584 households, 37.20% had children under the age of 18 living with them, 60.60% were married couples living together, 8.00% had a female householder with no husband present, and 28.30% were non-families. 23.60% of households were one person and 8.20% were one person aged 65 or older. The average household size was 2.59 and the average family size was 3.08.

The age distribution was 28.20% under the age of 18, 6.90% from 18 to 24, 32.10% from 25 to 44, 21.60% from 45 to 64, and 11.10% 65 or older. The median age was 35 years. For every 100 females, there were 97.70 males. For every 100 females age 18 and over, there were 93.80 males.

The median household income was $48,528 and the median family income was $58,293. Males had a median income of $37,243 versus $27,026 for females. The per capita income for the county was $22,970. About 4.00% of families and 5.60% of the population were below the poverty line, including 6.10% of those under age 18 and 7.10% of those age 65 or over.

‡ partly in Polk County

• Booneville
• Kennedy Station
• Moran
• Ortonville
• Panther
• Wiscotta
• Xenia
• Zook Spur

The population ranking of the following table is based on the 2020 census of Dallas County.

† county seat

Prior to 1932, Dallas County was strongly Republican in presidential elections. From 1932 to 1996, it was a swing county, having a Republican lean until 1960 & a Democratic lean from 1964 to 1996, especially after 1980. Since 2000, it has been consistently Republican, though no Republican presidential candidate has won over 58% of the vote nor has a Democrat won less than 41% since then.

• National Register of Historic Places listings in Dallas County, Iowa
• Raccoon River Valley Trail

• Meyer, Theodoric. "Two Iowa counties an hour apart show America’s growing political divide: Rural Decatur County has moved sharply red, while suburban Dallas County has shifted the other direction" Washington Post January 12, 2024, online

• Dallas County government's website (Archived April 4, 2005, at the Wayback Machine)
• HISTORY OF DALLAS COUNTY, IOWA 1879 Online book