20 Most Populated Counties in the US

Published on April 8, 2024 at 5:57 pm by Rabeeta Abbas in Lists, News

In this article, we take a look at the 20 Most Populated Counties in the US. If you want to, you can skip our detailed discussion of the topic and go directly to our shorter list of the 5 Most Populated Counties in the US.

According to the Census Bureau’s population estimates, in January 2024, the total population of the United States stood at 335,893,238, with an annual growth rate of 0.53%. In other words, the States will see an increase of 1,759,535 people in the total population by the end of this year. Speaking of the country’s population count, the United States is the third-largest country by population in the world. It is also the fourth-largest country by land area, covering 9,372,610 sq. kilometers.

Being a vast country with ample economic opportunities, the United States has been a magnet for immigrants looking for a better quality of life. Therefore, much of the population growth in the US is driven by net migration, which was 999,700 people in 2023, according to the World Bank data. Net migration in the US, combined with a fertility rate of 1.7 births per woman and a life expectancy of 80.8 years, has contributed significantly to its population.

However, there’s a great variation when it comes to population distribution across the country. The country consists of 50 states and the District of Columbia, these states are further divided into counties, which serve as administrative extensions of state governments. As of 2023 data, there were 3,196 counties in the US. Out of the 50 states, two states use the terms parishes and boroughs to refer to counties. These are Louisiana and Alaska respectively. Every state, on average, houses around 62 counties, with some states having more counties than others. (See also: 15 States with The Most Counties in the US).

Throughout these states and all the counties, the spread of population varies greatly. For instance, the Yukon-Koyukuk Census Area in Alaska is the largest county by land area of over 145,575.5 square miles but has a population of 5,129 people. On the contrary, New York County, which is one of the smallest counties in the US by area, has a population of nearly 1.6 million people, representing the discrepancy in the population distribution. If we look at the most densely populated counties, like New York County, we see that most Fortune 500 companies are headquartered in these areas, for instance, Pfizer Inc (NYSE:PFE) and Verizon Communications Inc. (NYSE:VZ).

Headquartered in New York City, which is the most populated city in the US, Pfizer Inc (NYSE:PFE) is an American multinational and one of the leading corporations in the pharmaceutical and biotechnology industry of the country. Last year, in 2023, Pfizer Inc (NYSE:PFE) acquired a global biotechnology company, Seagen Inc., for a total enterprise value of approximately $43 billion. With this acquisition, the company aims to achieve breakthroughs in cancer medicines that will drastically improve the lives of people around the world.

Meanwhile, Verizon Communications Inc. (NYSE:VZ), an American multinational conglomerate and one of the key players in the telecommunications industry, is also headquartered in New York City. In 2023, Verizon Communications Inc. (NYSE:VZ) invested $400,000 to support digital inclusion in small businesses and help entrepreneurs thrive in an increasingly digital economy.

On the other hand, Sony Group Corp (NYSE:SONY), one of the leading Japanese multinational companies, is headquartered in the most populated city of Japan, Tokyo. However, its American arm, Sony Corporation of America, is headquartered in New York City, NY. In February this year, Sony Group Corp (NYSE:SONY) announced the laying off of 900 employees in its PlayStation division, making it the largest company in the technology and gaming sector to announce layoffs.

In retrospect, the CEO of Sony Interactive Entertainment, Jim Ryan, said,

“While these are challenging times, it is not indicative of a lack of strength of our company, our brand, or our industry. Our goal is to remain agile and adaptable and to continue to focus on delivering the best gaming experiences possible now and in the future.”

20 Most Populated Counties in the US

Our Methodology

For our list of the 20 Most Populated Counties in the US, we have sourced data from the Census Bureau Vintage 2023. In particular, we looked at the Annual Resident Population Estimates for States and Counties between April 1 of 2020, and July 1 of 2023, which provided a list of US counties by population (all 3,196 counties) between all these years. We then shortlisted the 20 largest counties by population and arranged them in ascending order of their 2023 population estimates. All other information in the list has also been sourced from the Census Bureau.

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20 Most Populated Counties in the US

20. Middlesex County, Massachusetts

Population Estimates (2023): 1,623,952

Middlesex County, with a population of over 1.6 million residents, is one of the most populous counties in the US. Despite this, the county has experienced a slight population decline of 0.5% between 2020 and 2023. Moreover, 58.5% of residents of Middlesex County have attained a bachelor’s degree or higher, indicating a well-educated populace.

19. Wayne County, Michigan

Population Estimates (2023): 1,751,169

Ranked 19th, Wayne County presents a dynamic population and housing scene. As per 2022 Census Bureau US data, the county’s 790,946 housing units accommodate a mix of homeowners and renters. Wayne county comprises a 51.5% female population. (See also: 15 States with Highest Female to Male Ratio in the US).

18. Santa Clara County, California

Population Estimates (2023): 1,877,592

In Santa Clara County, 55.3% of the population has a bachelor’s degree or higher, meaning that the county boasts a highly educated populace. The racial composition according to Census Bureau data, is diverse, with almost half of the population identifying as White, 41.4% identifying as Asian, and 24.7% identifying as Hispanic or Latino. Furthermore, 4.9% of individuals under 65 in the county live with disabilities and 4.4% lack health insurance.

17. Broward County, Florida

Population Estimates (2023): 1,962,531

Ranked 17th, Broward County is home to a diverse population, with over half of the population identifying as White, 32.5% as Hispanic or Latino, and 4.0% as Asian, reflecting a melting pot of cultures and backgrounds. Between 2020 and 2023, the county saw a population increase of 0.9%.

16. Bexar County, Texas

Population Estimates (2023): 2,087,679

Bexar County, with a population exceeding 2 million, experienced a population surge of 3.9% between 2020 and 2023. Moreover, 64.7% of the county’s population actively participates in the civilian labor force. Despite this, with the median household earning of over $67,000, 15.6% of the people in Bexar County still live in poverty.

15. Tarrant County, Texas

Population Estimates (2023): 2,182,947

Tarrant County, with a land area of 865.2 sq. miles is the 179th largest county in the state of Texas by total area. Around 16.2% of people in the county do not have healthcare coverage, including 19.9% of people under age 65. Tarrant County has an employment rate of 65.8%, and 68.5% of the total population actively participates in the civilian labor force.

14. San Bernardino County, California

Population Estimates (2023): 2,195,611

San Bernardino County, with a population of nearly 2.2 million, and a land area of 20,068.2 sq. miles, is the largest county in California by land area. It has a population comprising 75.3% White, 8.9% Asian, and 56.2% Hispanic or Latino people. In terms of housing, there are over 742,000 units, with 61.1% being owner-occupied.

13. Queens County, New York

Population Estimates (2023): 2,252,196

Queens County, with 108.7 sq. miles of land area, is the 4th smallest county in New York. The median household income in the county is $80,557, which is $1,000 higher than the state. Also, the poverty rate among the people of Queens County is 1.3% less than in the whole of New York.

12. King County, Washington

Population Estimates (2023): 2,271,380

Between 2020 and 2022, King County saw a population decline of 0.2%. However, between 2022 and 2023, the county saw a significant increase in population of 0.1%, bringing the total population count up from 2,265,311 to 2,271,380 people. Furthermore, there are approximately 916,270 households in the county, with an average of 2 people per household. It is the 11th largest county in Washington state by total area.

11. Clark County, Nevada

Population Estimates (2023): 2,336,573

Clark County, famously home to the Las Vegas Strip, draws numerous tourists each year with its vast array of casinos and hotels. Amidst the hustle and bustle of this tourist hotspot, over 86% of adults have completed high school, and more than a quarter hold bachelor’s degrees or higher. Clark County is the 6th largest county by population in Nevada, and the 11th largest county by population by population.

10. Riverside County, California

Population Estimates (2023): 2,492,442

10th on the list of most populated counties in the US, Riverside County is the 4th largest county in California by total area. The median household income in the county stands at around $86,748 and the employment rate stands at 58.6%. Moreover, 14.6% of residents are employed in local, state, and federal government roles.

9. Kings County, New York

Population Estimates (2023): 2,561,225

The third smallest county in New York, Kings County is the 9th largest county in the US by population. Notably, 42.4% of the county residents hold a bachelor’s degree or higher, which showcases their commitment to higher learning. As per the Census Bureau, the county’s workforce also has some degree of variety, with 62.2% in private companies, 4.2% self-employed, 13.0% in private not-for-profits, 14.1% in government roles, and 6.5% self-employed or unpaid family workers.

8. Dallas County, Texas

Population Estimates (2023): 2,606,358

The 177th largest county in Texas by total area, Dallas County ranks 8th among the 10 largest counties in the US by population. If we look at the racial diversity, the county houses 65.5% White folks, 7.2% Asians, and 41.5% Hispanics or Latinos. Moreover, the employment demographics suggest that about 9.5% of employed individuals work for the government, while 66.5% are part of the civilian workforce.

7. Miami-Dade County, Florida

Population Estimates (2023): 2,686,867

Miami-Dade County, the 3rd largest county in Florida by total area, saw a slight dip of 0.6% in population from 2020 to 2023. Still, it houses the 7th highest number of people as compared to the other 3,196 counties in the States. Furthermore, even though the median household income exceeds the $64,000 figure, 14.5% of residents of Miami-Dade County are struggling with poverty.

6. Orange County, California

Population Estimates (2023): 3,135,755

Positioning itself as the first county on the list crossing the 3 million resident count, Orange County is one of the top 20 US counties with the highest population. Between 2020 and 2022, Orange County saw a population decline of 1.1%, and between 2022 and 2023, the county saw a further 1.6% decline, bringing the total population count down from 3,150,372 to 3,135,755 people. It is the 47th largest county in California by land area.

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