This statistic shows the top twenty-five fastest growing counties in the United States as of July 1, 2019, by change in population from April 1, 2010. On July 1, 2019, the fastest growing county with 10,000 or more population in the United States was Williams County in North Dakota with a growth rate of 67.8 percent.

This statistic shows the 25 largest counties in the United States in 2022, by population. In 2022, about 9.72 million people were estimated to be living in Los Angeles County, California.

Additional information on urbanization in the United States

Urbanization is defined as the process by which cities grow or by which societies become more urban. Rural to urban migration in the United States, and around the world, is often undertaken in the search for employment or to enjoy greater access to services such as healthcare. The largest cities in the United States are steadily growing. Given their size, incremental increases yield considerable numerical gains as seen by New York increasing by 69,777 people in 2011, the most of any city. However in terms of percentage growth, smaller cities outside the main centers are growing the fastest, such as Georgetown city and Leander city in Texas.

Urbanization has increased slowly in the United States, rising from 80.77 percent of the population living in urban areas in 2010 to 82.66 percent in 2020. In 2018, the United States ranked 14th in a ranking of countries based on their degree of urbanization. Unlike fully urbanized countries such as Singapore and Hong Kong, the United States maintains a sizeable agricultural industry. Although technological developments have reduced demands for rural labor, labor in the industry and supporting services are still required.

This multi-scale map shows counts of the total population the US. Data is from U.S. Census Bureau's 2020 PL 94-171 data for county, tract, block group, and block.County and metro area highlights:The largest county in the United States in 2020 remains Los Angeles County with over 10 million people.The largest city (incorporated place) in the United States in 2020 remains New York with 8.8 million people.312 of the 384 U.S. metro areas gained population between 2010 and 2020.The fastest-growing U.S. metro area between the 2010 Census and 2020 Census was The Villages, FL, which grew 39% from about 93,000 people to about 130,000 people.72 U.S. metro areas lost population from the 2010 Census to the 2020 Census. The U.S. metro areas with the largest percentage declines were Pine Bluff, AR, and Danville, IL, at -12.5 percent and -9.1 percent, respectively.View more 2020 Census statistics highlights on local populations changes.

In the Cook Islands in 2024, the population decreased by about 2.24 percent compared to the previous year, making it the country with the highest population decline rate in 2024. Of the 20 countries with the highest rate of population decline, the majority are island nations, where emigration rates are high (especially to Australia, New Zealand, and the United States), or they are located in Eastern Europe, which suffers from a combination of high emigration rates and low birth rates.