Los Angeles County Had the Biggest Population Decline in the Nation. Here’s What’s Driving It

Los Angeles County is losing people faster than any other county in the country right now. But why?

This is not about people suddenly giving up on Los Angeles. It is actually about what happens when a place already bleeding residents to domestic out-migration gets less help from the one force that had been cushioning the fall: international migration. Add California’s deeper affordability crisis, slower birth rates, and an aging population, and the result starts to sound logical.

According to new U.S. Census Bureau estimates, Los Angeles County lost 53,934 residents between July 1, 2024, and July 1, 2025, the largest numeric decline among counties in the United States. The county’s estimated population fell from 9,748,868 to 9,694,934. That is a drop of about 0.5%, which means L.A. remains by far the nation’s most populous county, but it also means the county is still moving in the wrong direction.

The biggest reason is not mysterious at all

The clearest national explanation came from the Census Bureau itself. Population growth slowed across much of the country between 2024 and 2025, and the slowdown hit the biggest counties hardest. Those large counties tend to lose people through domestic migration, meaning more residents move out to other parts of the country than move in from elsewhere in the U.S. In normal years, many of them make up for that through net international migration and natural increase. In 2025, that buffer weakened.

That being said, Census data show L.A. still had a positive natural increase, with 22,581 more births than deaths, and still posted substantial net international migration, with 91,048 more international arrivals than departures. But those gains were overwhelmed by a net domestic migration loss of 76,146. Total net migration remained positive at 14,902, but it was not enough to offset the county’s broader trend lines once the year’s other adjustments were factored in, resulting in an overall loss of 53,934 residents.

Put differently, L.A. County did not suddenly empty out because nobody wanted to come. It shrank because too many people were still leaving for elsewhere in the U.S., and the international inflow that often softens that damage was lower than before in counties across the country.

California’s deeper math is making the problem worse

That data sits inside a larger California one. The Public Policy Institute of California has warned for years that the state’s population slowdown results from four forces working together: births, deaths, international immigration, and interstate migration. The pandemic intensified each one, but the underlying pattern predates COVID. Growth had already been slowing for years.

The most obvious long-term driver is domestic out-migration. PPIC found that Californians have been leaving for states like Texas, Oregon, Nevada, and Arizona, with housing costs playing an outsized role. In one PPIC survey, about 34% of Californians said they were considering leaving the state because of housing costs. The pressure falls hardest on lower- and middle-income households, but it is not confined to them. An increasing share of higher-income Californians has also been leaving, in part because remote work makes it easier to do so.

The California Department of Finance’s newest estimate points in the same direction. The state grew only 0.05% in the year ending July 1, 2025. Net international migration fell sharply to 126,000, about half the prior year’s level, while net domestic migration became more negative again, reaching a loss of 216,000 people. Natural increase added 108,300 people, but the state still ended up with total net migration losses outweighing many of those gains.

That statewide pattern helps explain why Los Angeles County’s numbers look so different now.

People are not always leaving the region. They are often running away from high prices and towards affordability

Population loss in L.A. County does not necessarily mean people are abandoning Southern California altogether. In many cases, they are moving outward, looking for cheaper versions of proximity.

Riverside County’s population rose from 2,529,933 in 2024 to 2,544,916 in 2025, while San Bernardino County grew from 2,214,281 to 2,224,091. Together, those two neighboring counties added 24,793 residents over the same period that L.A. County posted the nation’s largest numeric decline.

For many households, this is less a rejection of Southern California than a relocation within it. The jobs, family networks, and cultural pull may still be here. The rent, however, has become increasingly unjustifiable.

Birth rates and aging are also key

Housing reaches the headlines because, well, it should. But demography is doing its own slow, unforgiving work behind the scenes.

PPIC notes that California’s birth rate has fallen sharply over time and is now among the lowest in the country. At the same time, the state is aging. Declining fertility, longer life expectancy, and the aging of the baby boom generation mean deaths are likely to continue rising over time as the population ages. That means that, with time, natural increase, one of the traditional engines of growth, becomes harder to sustain when there are fewer births and more older residents.

So even when L.A. County still posts more births than deaths, the long-run direction is more fragile than it once was. The old California formula, rapid growth powered by migration and a younger age structure, no longer works the way it used to.

Finally, this is also about what Los Angeles still offers in return

There lies the unavoidable question: what does Los Angeles promise, and for whom does that promise still pencil out?

For decades, people accepted the cost of living here because the tradeoff felt worth it. The jobs, industries, weather, culture… They were all here. But when rent devours wages, homeownership drifts out of reach, and work itself becomes more geographically flexible, that old bargain gets weaker. The county is still huge, of course it is. But staying here now requires a calculation that more people appear unwilling or unable to make.