Maricopa County Population Growth Largest In Nation For Second Consecutive Year

Population growth in Maricopa County was largest in nation for second consecutive year.

After some of the nation’s most populous counties experienced significant outmigration and population declines in 2021, overall patterns of population growth and decline are moving towards pre-pandemic rates for the nation’s 3,144 counties according to the U.S. Census Bureau’s Vintage 2022 estimates of population and components of change released today. All 10 of the top fastest-growing counties were in the South or West.

“The migration and growth patterns for counties edged closer to pre-pandemic levels this year,” said Dr. Christine Hartley, assistant division chief for estimates and projections in the Census Bureau’s population division. “Some urban counties, such as Dallas and San Francisco, saw domestic outmigration at a slower pace between 2021 and 2022, compared to the prior year. Meanwhile, many counties with large universities saw their populations fully rebound this year as students returned.”


Whitman County, Washington, home to Washington State University, saw its population drop by 9.6% between 2020 and 2021 but then grow by 10.1% last year—the most of any county above 20,000 in population. Whitman County’s change is just one example of the many college counties that saw a rebound in the last year after a lull during the COVID-19 pandemic.

This is similar to the pattern observed by many metropolitan counties in the South and West, where many impacts experienced during the pandemic are either reverting to near pre-pandemic levels or making a full recovery. For example, Dallas County, Texas, the eighth most populous county in the U.S. in 2022, lost over 22,000 (-0.8%) people between 2020 and 2021, but between 2021 and 2022 gained nearly 13,000 (0.5%) people—the fastest gains the county has seen since 2017.

Counties

As of July 1, 2022, just under one-half (48.7%) of counties were under 25,000 in total resident population, while 19.5% of counties had a population of 100,000 or more. Only 47 (1.5%) counties had a population of 1 million or more.

Population Size of Counties on July 1, 2022
Size group Number (percent)
100,000 or higher 613 (19.5%)
50,000 to 99,999 385 (12.2%)
25,000 to 49,999 615 (19.6%)
10,000 to 24,999 793 (25.2%)
Under 10,000 738 (23.5%)
Source: U.S. Census Bureau, Vintage 2022 Population Estimates

Population Change

Over one-half of all counties (52.5%) grew between 2021 and 2022, down from 55.7% of counties the prior year. At the same time, 1,482 (47.1%) declined and 11 counties (0.3%) saw no change in population.

The smallest counties nationally, those with populations below 10,000, experienced more population loss (60.8%) than gains (38.3%); while the largest counties, having populations at or greater than 100,000, largely experienced population increases (68%).

Population Change in Counties: 2021 to 2022
Size group Gain No change Loss
100,000 or higher 417 (68.0%) 0 (0.0%) 196 (32.0%)
50,000 to 99,999 242 (62.9%) 1 (0.3%) 142 (36.9%)
25,000 to 49,999 335 (54.5%) 0 (0.0%) 280 (45.5%)
10,000 to 24,999 374 (47.2%) 4 (0.5%) 415 (52.3%)
Under 10,000 283 (38.3%) 6 (0.8%) 449 (60.8%)
Source: U.S. Census Bureau, Vintage 2022 Population Estimates

Fastest Growing

Whitman County, Washington, was the fastest-growing county between 2021 and 2022.

  • One-half of the top 10 fastest-growing counties were in Texas: Kaufman County (8.9%), Rockwall County (5.7%), Parker County (5.6%), Comal County (5.6%) and Chambers County (5.3%).
  • The remaining fastest-growing counties were in Florida (Sumter County, 7.5%), Georgia (Dawson and Lumpkin Counties, both with 5.8%), and North Carolina (Brunswick County, 5.7%).

Largest Gaining

Maricopa County, Arizona, remained the largest-gaining county in the nation, adding 56,831 residents in 2022, a gain of 1.3% since 2021. Domestic migration was the component of population change (i.e., births, deaths and migration), which made the largest contribution to Maricopa County’s growth. Harris County, Texas, had the second-largest gain last year, up 45,626. Texas was home to 6 of the top 10 largest-gaining counties in 2022. Harris, Collin, Denton, Fort Bend, Bexar and Montgomery Counties gained a combined 209,182 residents. Three Florida counties (Polk, Lee and Hillsborough) also were among the largest gaining in 2022, collectively adding 92,848 residents.

Largest Declining

Los Angeles County, California, had the largest population decline in 2022, decreasing by 90,704, continuing a downward trend as the state lost roughly twice that amount (180,394) in 2021. Population declines lessened for some other urban counties that had seen considerable net domestic outmigration and population decline in 2021. New York County, New York, which had a population decline of 98,505 in 2021 due largely to net domestic outmigration, had population growth of 17,472 this past year. Collectively, this year’s 10 counties with the largest population declines lost 378,177 people, down significantly when compared to last year’s collective drop of 709,775 for that year’s 10 counties with the largest population declines.

Most Populous

Los Angeles County, California, (9,721,138) and Cook County, Illinois, (5,109,292) remain the two most populous counties in the nation. Reflecting longstanding regional population shifts, the nation’s most populous counties are increasingly located in the South and West. In 2022, 63 of the country’s 100 most populous counties were located in the South and West, up from 61 in the prior year. This is compared to 2010, when 58 of the country’s largest counties were in the South and West. The South and West had 51 of the largest counties in 1990 and 50 in 1980.

Components of Change

Domestic Migration

Patterns of domestic migration in 2022 were notably different than 2021. During the height of the pandemic, many small counties experienced higher levels of domestic migration, while many large counties saw lower levels of domestic migration. This pattern has reversed between 2021 and 2022, where many of the small counties that experienced increases in domestic migration saw that pattern slow down. In the meantime, many large counties, particularly in the South and West, observed an uptick in domestic migration.

Sixty percent of U.S. counties had positive net domestic migration in 2022 compared to 63.3 in 2021. All counties in Delaware, Maine and New Hampshire had positive net domestic migration. The two counties with the highest amounts of net domestic migration were Maricopa County, Arizona, (33,305) and Collin County, Texas, (29,696). There were seven states where 75% of counties experienced negative net domestic migration, with Illinois having the largest percentage (89%) of its counties lose residents via domestic migration. The counties with the highest negative net domestic migration were Los Angeles County, California, (-142,953) and Cook County, Illinois, (-94,344).

While several large counties, such as Los Angeles County, California, lost a large number of people through domestic migration in the last year, changes in patterns in domestic migration between 2021 and 2022 meant they lost fewer people compared to the year before. Los Angeles County lost 142,953 people via net domestic migration between 2021 and 2022, compared to 2020 to 2021 when it lost 194,804 people due to net domestic migration.

New York County (Manhattan), New York, had a slight net domestic migration of 2,908 this year, a sharp turnaround from net domestic outmigration of -98,566 the prior year.

San Francisco County, California, had net domestic outmigration of -9,421 in 2022, compared to -57,611 the prior year.

Finally, King County, Washington, (home to Seattle) had net domestic outmigration of -16,035 in 2022, compared to -37,655 in 2021.

Net International Migration

Net international migration patterns for counties remained relatively the same in 2022 as in 2021, with 2,462 counties (78%) seeing positive net international migration. However, with the rebound in net international migration for the nation, the levels for counties were often considerably higher than the prior year. For instance, net international migration in Miami-Dade County, Florida, the top ranked county for net international migration in 2022, increased from 15,108 between 2020 and 2021, to over double that (39,170) the following year. Similarly, in second-ranked Harris County, Texas, net international migration more than doubled in size – 13,919 between 2020 and 2021, it grew to 37,268 between 2021 and 2022.

Natural Decrease and Increase

In 2022, 2,336 (74.3) counties had natural decrease (more deaths than births), compared to 2,368 in 2021. The incidence of natural decrease remains historically high. Natural decrease counties are found nationwide but are especially prevalent in some states. While Maine was the only state where all counties experienced natural decrease, West Virginia also had a high frequency of natural decrease – with deaths outnumbering births in 54 of 55 of its counties. Seven of the 10 counties with the highest amount of natural decrease were in Florida, with Pinellas County topping the list with -6,468.

Natural increase (births exceeding deaths) occurred in 791 counties (25.2%) last year. Five of the top 10 counties in natural increase were in Texas, with Harris County having the highest in the nation (30,117).

Top 10 Most Populous Counties – 2022

Top 10 Most Populous Counties: 2022
Rank State County April 1, 2020
(Estimates Base)
July 1, 2021 July 1, 2022
1 California Los Angeles County 10,014,042 9,811,842 9,721,138
2 Illinois Cook County 5,275,522 5,177,606 5,109,292
3 Texas Harris County 4,731,129 4,735,287 4,780,913
4 Arizona Maricopa County 4,420,574 4,494,693 4,551,524
5 California San Diego County 3,298,635 3,274,954 3,276,208
6 California Orange County 3,186,979 3,161,005 3,151,184
7 Florida Miami-Dade County 2,701,762 2,670,421 2,673,837
8 Texas Dallas County 2,611,491 2,587,954 2,600,840
9 New York Kings County 2,736,075 2,637,486 2,590,516
10 California Riverside County 2,418,177 2,453,178 2,473,902
Source: U.S. Census Bureau, Vintage 2022 Population Estimates

Top 10 Counties in Numeric Growth (Annual)

Top 10 Counties in Numeric Growth, 2021 to 2022
Rank State County April 1, 2020
(Estimates Base)
July 1, 2021 July 1, 2022 Numeric Growth
1 Arizona Maricopa County 4,420,574 4,494,693 4,551,524 56,831
2 Texas Harris County 4,731,129 4,735,287 4,780,913 45,626
3 Texas Collin County 1,066,465 1,114,450 1,158,696 44,246
4 Texas Denton County 906,405 943,857 977,281 33,424
5 Florida Polk County 725,041 755,179 787,404 32,225
6 Florida Lee County 760,820 790,676 822,453 31,777
7 Texas Fort Bend County 822,779 860,124 889,146 29,022
8 Florida Hillsborough County 1,459,773 1,484,455 1,513,301 28,846
9 Texas Bexar County 2,009,322 2,030,895 2,059,530 28,635
10 Texas Montgomery County 620,451 650,261 678,490 28,229
Source: U.S. Census Bureau, Vintage 2022 Population Estimates

Top 10 Counties in Numeric Decline (Annual)


Top 10 Counties in Numeric Decline, 2021 to 2022
Rank State County April 1, 2020
(Estimates Base) 
July 1, 2021 July 1, 2022 Numeric Decline
1 California Los Angeles County 10,014,042 9,811,842 9,721,138 -90,704
2 Illinois Cook County 5,275,522 5,177,606 5,109,292 -68,314
3 New York Queens County 2,405,464 2,328,141 2,278,029 -50,112
4 New York Kings County 2,736,075 2,637,486 2,590,516 -46,970
5 New York Bronx County 1,472,656 1,421,089 1,379,946 -41,143
6 Pennsylvania Philadelphia County 1,603,799 1,589,480 1,567,258 -22,222
7 Michigan Wayne County 1,793,549 1,773,073 1,757,043 -16,030
8 California Santa Clara County 1,936,274 1,886,595 1,870,945 -15,650
9 California Alameda County 1,682,331 1,643,837 1,628,997 -14,840
10 Pennsylvania Allegheny County 1,250,585 1,245,445 1,233,253 -12,192
Source: U.S. Census Bureau, Vintage 2022 Population Estimates

Top 10 Counties in Percent Decline (Annual)

Top 10 Counties in Percent Decline, 2021 to 2022
Resident Population of 20,000 or more in 2021 and 2022
Rank State County April 1, 2020
(Estimates Base)
July 1, 2021 July 1, 2022 Percent Decline
1 California Lassen County 32,730 31,813 29,904 -6.0%
2 Louisiana St. John the Baptist Parish 42,477 42,021 39,864 -5.1%
3 Louisiana Terrebonne Parish 109,583 109,013 104,786 -3.9%
4 Louisiana Plaquemines Parish 23,515 23,284 22,516 -3.3%
5 Florida Baker County 28,263 28,673 27,803 -3.0%
6 Mississippi Leflore County 28,348 27,398 26,570 -3.0%
7 New York Bronx County 1,472,656 1,421,089 1,379,946 -2.9%
8 Louisiana St. Charles Parish 52,548 52,405 50,998 -2.7%
9 Mississippi Bolivar County 30,973 30,180 29,370 -2.7%
10 Florida Bradford County 28,306 28,050 27,313 -2.6%
Source: U.S. Census Bureau, Vintage 2022 Population Estimates