L.A. County Leads Nation in Population Loss as Immigration Slowdown Reshapes America

The Numbers

Los Angeles County, the most populous county in the United States, shed nearly 54,000 residents between July 1, 2024, and July 1, 2025, according to Vintage 2025 population estimates released on March 26 by the U.S. Census Bureau. That figure represents the largest absolute population decline of any county in the nation during the period.

The county, which had more than 10 million residents at the time of the 2020 Census, is now estimated to have fewer than 9.7 million people as of mid-2025 — a cumulative loss of more than 322,000 residents since the 2019-2020 estimates, according to Census Bureau data reported by multiple outlets.

The second-largest absolute decline belonged to Pinellas County, Florida — home to St. Petersburg — which lost almost 12,000 residents. The Census Bureau attributed Pinellas County's losses partly to Hurricanes Helene and Milton, which struck Gulf Coast communities in the fall of 2024.

A National Pattern

L.A. County's decline is not an isolated phenomenon. The Census Bureau's release documented a sweeping nationwide slowdown in population growth driven primarily by reduced net international migration (NIM).

According to the bureau, nine out of 10 U.S. counties experienced lower NIM levels between July 1, 2024, and June 30, 2025, compared to the prior year. The remaining 10% of counties saw no change — meaning not a single county in the country experienced an increase in international migration.

The consequences were widespread. Among the 2,066 counties that grew between 2023 and 2024, nearly eight in 10 saw their growth slow or reverse direction in 2025. Population growth in metro areas fell from an average of 1.1% in 2024 to 0.6% in 2025. In about 75% of all counties, overall population growth either slowed or turned negative, according to the New York Times' analysis of the data.

Bloomberg reported that four in 10 U.S. counties shrank outright in 2025.

Border Communities Hit Hardest

The steepest declines in population growth rates were concentrated along the U.S.-Mexico border. The Census Bureau identified three metro areas with the most dramatic reversals:

• Laredo, Texas: Growth rate fell from 3.2% in the 2023-2024 period to 0.2% in 2024-2025
• Yuma, Arizona: Growth rate fell from 3.3% to 1.4%
• El Centro, California: Growth rate fell from 1.2% to negative 0.7%

Helen You, interim director of the Texas Demographic Center, noted in remarks reported by CBS News that the data suggests "a sharper rise-and-fall effect in border regions, where international migration plays a more central role in year-to-year population change."

Why It Matters

With an aging population and birth rates declining over the past two decades, immigration has become a critical driver of population growth in many American communities. Kenneth Johnson, senior demographer at the University of New Hampshire, explained the dynamic in remarks to CBS News: "With so little natural increase, migration determines whether an area grows or declines, particularly in the big metro cores that have continuous domestic out-migration and are dependent on immigration."

Census Bureau demographer George M. Hayward put it in similar terms in the bureau's official press release: "The nation's largest counties like those in the New York metro area are often international migration hubs, gaining large numbers of international migrants and losing people that move to other parts of the country via domestic migration. With fewer gains from international migration, these types of counties saw their population growth diminish or even turn into loss."

The New York metro area, which had grown by the most people of any metro area in 2024, fell to 13th place in 2025 as immigrant arrivals dropped.

California's Specific Pressures

For L.A. County, the immigration slowdown compounded pre-existing demographic pressures that have been building for years. During the COVID-19 pandemic, California experienced its first population decline since gaining statehood in 1850 and lost a congressional seat, according to the Public Policy Institute of California (PPIC).

Dowell Myers, a demographer and professor emeritus at the University of Southern California, described the precariousness of the situation in remarks reported by OAN: "All these forces are largely invisible to the public because the population over time has been pretty stable. But beneath the surface, your population has been propped up by immigration for years, and if you pull out the prop, watch what happens. You'll have problems finding workers for anything – restaurants, daycare, finding a gardener, hospital workers."

San Diego County also saw a decline of more than 5,300 residents during the period. PPIC has warned that if recent trends continue, California could lose as many as four of its 52 congressional seats in the 2030 apportionment.

Meanwhile, neighboring Riverside and San Bernardino counties, as well as the Las Vegas area, saw population increases — suggesting that some departing L.A. residents are relocating to more affordable areas within driving distance rather than leaving the region entirely.

Where People Are Going

The Census data reveals a continued nationwide pattern of population shifting from large urban cores to smaller communities and exurbs. Collectively, the 50 counties with populations of 1 million or more experienced a net domestic migration loss of 637,634 people. Large counties (50,000 to 999,999 in population) gained 533,766 through domestic migration, while medium-sized counties (15,000 to 49,999) gained 95,095 and even small counties (under 15,000) saw a slight gain of 8,773.

The fastest-growing metro areas in 2025 were led by Houston and Dallas-Fort Worth, followed by Atlanta, Phoenix, and the Charlotte, North Carolina, metro area. Among smaller metros, Ocala, Florida — located 80 miles northwest of Orlando — led the nation with a 3.4% growth rate, followed by Myrtle Beach, South Carolina, and Spartanburg, South Carolina.

The far-out suburbs were the top destinations for domestic movers, led by Collin County, Texas (outside Dallas); Montgomery County, Texas (outside Houston); Pinal County, Arizona (outside Phoenix); and Pasco and Polk counties outside Tampa. The Census Bureau attributed the exurban growth pattern to an after-effect of the COVID-19 pandemic, as rising housing costs drove people farther from cities and remote work allowed many to do their jobs from home.

The Bigger Picture

The data arrives at a politically charged moment. The population estimates cover the first months of the Trump administration's second term and its immigration enforcement efforts. The bureau's data does not attempt to assign policy causation, but the temporal overlap is clear: the period during which immigration fell in every metro area in America coincides with expanded enforcement actions and border policies.

For communities that have relied on immigration to offset domestic outmigration and declining birth rates, the implications extend beyond politics to practical questions of workforce availability, economic vitality, and political representation. As Myers noted, the consequences of pulling out the immigration "prop" may be felt across sectors from healthcare to food service — and ultimately at the ballot box, as congressional apportionment follows population.