Newly released U.S. Census Bureau data has revealed Harris County became the third most populous county nationwide in 2024, and had the highest year-over-year growth rate from 2023.
The new population report, published March 13, estimated year-over-year population data from 2023 to 2024 across all 3,144 U.S. counties, and 387 metro areas.
Harris County's numeric growth rate outpaced all other U.S. counties from July 1, 2023 to July 1, 2024, the report found. The Census Bureau estimated Harris County's population grew by 105,852 people year-over-year, bringing the total population to 5,009,302 residents. That's around a 2.16 percent growth rate.
Los Angeles County, California (No. 1) and Illinois' Cook County (No. 2) are the only two U.S. counties that have larger populations than Harris County. Los Angeles County now boasts a population of nearly 9.76 million, while Cook County's has increased to more than 5.18 million people
The top 10 most populous counties in the U.S. are:
- No. 1 – Los Angles County, California
- No. 2 – Cook County, Illinois
- No. 3 – Harris County, Texas
- No. 4 – Maricopa County, Arizona
- No. 5 – San Diego County, California
- No. 6 – Orange County, California
- No. 7 – Miami-Dade County, Florida
- No. 8 – Dallas County, Texas
- No. 9 – Kings County, New York
- No. 10 – Riverside County, California
Montgomery County also ranked among the top 10 U.S. counties with the highest numeric growth, ranking 9th nationally after gaining 34,268 residents from 2023 to 2024. Montgomery County's population has now grown to 749,613 people.
In the report's national comparison of counties with the largest population growth by percentage, Montgomery County ranked No. 7 with a year-over-year growth rate of 4.8 percent.
Most populated U.S. metro areas
The U.S. Census Bureau additionally found Houston-Pasadena-The Woodlands nearly led the nation as the second-fastest growing metro area in 2024.
From July 2023 to July 2024, the Houston metro added 198,171 residents to bring the total population to 7,796,182.
New York-Newark-Jersey City was the only metro area to outpace Houston's growth during the one-year period. The New York-New Jersey metro added 213,403 new residents, which brought the total population to over 19.94 million last year.
Kristie Wilder, a Census Bureau Population Division demographer, said in the report that the nation's population growth in its major metros was largely impacted by international migration, rather than changes in birth rates.
"While births continue to contribute to overall growth, rising net international migration is offsetting the ongoing net domestic outmigration we see in many of these areas," Wilder said.
Dallas-Fort Worth-Arlington was right behind Houston as the third-fastest growing U.S. metro in 2024. The Metroplex gained 177,922 residents last year, and now has a total population of more than 8.34 million.
The top 10 U.S. metros with the highest numeric growth from 2023 to 2024 are:
- No. 1 – New York-Newark-Jersey City, New York-New Jersey
- No. 2 – Houston-Pasadena-The Woodlands, Texas
- No. 3 – Dallas-Fort Worth-Arlington, Texas
- No. 4 – Miami-Fort Lauderdale-West Palm Beach, Florida
- No. 5 – Washington-Arlington-Alexandria, D.C.-Virginia-Maryland-West Virginia
- No. 6 – Phoenix-Mesa-Chandler, Arizona
- No. 7 – Orlando-Kissimmee-Sanford, Florida
- No. 8 – Atlanta-Sandy Springs-Roswell, Georgia
- No. 9 – Chicago-Naperville-Elgin, Illinois-Indiana
- No. 10 – Seattle-Tacoma-Bellevue, Washington
