Dallas City is a city in Hancock and Henderson counties in the U.S. state of Illinois. The population was 945 at the 2010 census, a decline from 1,055 in 2000.
The Hancock County portion of Dallas City is part of the Fort Madison–Keokuk, IA–IL–MO Micropolitan Statistical Area, and the Henderson County portion of Dallas City is part of the Burlington, IA–IL Micropolitan Statistical Area.
Dallas City was laid out in 1848, and named in honor of George Mifflin Dallas, 11th Vice President of the United States of America, from 1845 to 1849. A post office has been in operation at Dallas City since 1850.
Dallas City is located at 40°38′12″N 91°9′55″W (40.636565, -91.165256).
According to the 2010 census, Dallas City has a total area of 3.272 square miles (8.47 km2), of which 2.37 square miles (6.14 km2) (or 72.43%) is land and 0.902 square miles (2.34 km2) (or 27.57%) is water.
As of the census of 2000, there were 1,055 people, 466 households, and 301 families residing in the city. The population density was 444.2 people per square mile (171.2/km²). There were 503 housing units at an average density of 211.8 per square mile (81.6/km²). The racial makeup of the city was 99.72% White, 0.09% Native American, and 0.19% from two or more races. Hispanic or Latino of any race were 0.57% of the population.
There were 466 households out of which 23.2% had children under the age of 18 living with them, 55.4% were married couples living together, 7.9% had a female householder with no husband present, and 35.2% were non-families.