LeClaire is a city in Scott County, Iowa, United States. The population was 4,710 in 2020, a 65.4% increase from 2,847 in 2000, making it one o…LeClaire is a city in Scott County, Iowa, United States. The population was 4,710 in 2020, a 65.4% increase from 2,847 in 2000, making it one of the fastest-growing communities in the Quad Cities. LeClaire is considered a suburb and part of the Quad Cities Metropolitan Area, which includes the area of Davenport and Bettendorf, Iowa, and Rock Island, Moline, and East Moline, Illinois.