By every available measure, California’s population is growing again, albeit modestly. The dark years following the COVID-19 pandemic, and the steep population loss that accompanied them, appear to be in the rear view.
It’s what lies ahead, though, that worries researchers and those active in the vast migrant communities that help comprise the Golden State’s 39.4 million residents. Some of President Donald Trump’s more extreme immigration proposals could pump the brakes on California’s return to population normalcy — and have profound political and financial consequences for everyone who remains here, though it’s not clear if that is Trump’s goal.
By threatening mass deportation of undocumented residents, by attempting to end birthright citizenship through executive fiat and by dangling the possibility of forcing a citizenship question into national census-taking, the second Trump administration has already put immigrant communities on high alert.
“Almost one in three workers in California is an immigrant,” said Hans Johnson, a senior fellow at the Public Policy Institute of California, which closely tracks the state’s population shifts. “Most of those are legal residents and legally allowed to work here. A small share, but not nothing, is unauthorized — and the numbers are not tiny.
“If the administration was able to deport every unauthorized immigrant in California — and I don’t know that they want to do that, to be clear — it would be a huge problem for our agricultural, hospitality and construction industries and others,” Johnson said.
Depending upon what is ultimately allowed by the courts (and which priorities hold Trump’s interest long enough for him to push them further), one result could be a voluntary exodus of Californians because of their immigrant status. According to the Pew Research Center, the state was home in 2022 to 1.8 million undocumented immigrants, the most in the country. (The states with the next highest tallies are Texas at 1.6 million and Florida at 1.2 million.)
Such an exodus would potentially tear apart families; according to the California Immigrant Data Portal, more than 3.3 million people in the state in 2021 lived in a household that included at least one undocumented immigrant. And at the federal level, state population determines both representation and, critically, federal funding.
When California lost a seat in the U.S. House of Representatives in 2021, it was a result 20 years in the making. Since roughly 2000, the state has been experiencing its slowest rates of population growth on record, according to the Public Policy Institute of California.
There are multiple reasons for that, including lower fertility and birth rates, higher death rates and a dropoff in international migration. In recent years, especially during and just after the pandemic, the biggest driver was the number of people leaving California for other states, often because they were allowed to work remotely and sought cheaper housing, Johnson said.
Some of those conditions have begun to stabilize. California’s net out-migration — more people leaving than moving here — has dropped significantly in each of the last three years, though it remains at high levels relative to the state’s history. Death rates are returning to normal levels after spiking at the height of COVID’s spread. Although fewer people are coming to the state from elsewhere in the world than in previous decades, that figure is still high enough to drive a net gain in population, as Gov. Gavin Newsom’s office was happy to note last year.
Still, California’s population growth lags behind the national average, and there are representational and financial implications from that. At the end of 2023, the Brennan Center for Justice estimated that if current trends held, the state would lose four more seats in the House in the 2030 congressional redistricting, a process that occurs once a decade. That would mean that since 2020, California’s House representation would have taken a nearly 10% hit, from 53 seats to 48.
With the state rebounding somewhat, it’s difficult to know whether the center’s estimates will prove out — but every seat counts. Not only would California lose representation in the House, but it also would lose votes in the Electoral College, which ultimately determines the presidency.
The same Census population data that leads to redistricting, meanwhile, is used to figure out how much money each state receives from the federal government. As California’s share of the U.S. population declines, so does its share of federal funding. Last year, $170.6 billion — more than a third of the state’s budget — came from federal funds.
It’s too early to know what effect Trump’s policies will have on California’s immigrant population or the state’s finances, in part because it isn’t yet certain what his administration will be allowed or motivated to actually do. But there are ominous possibilities.
“It’s not clear how it’s going to completely unfold, and how large the numbers might be in terms of deportations,” Johnson said. “But one factor to keep in mind is how important immigrants are to our labor force.”
Like the rest of the country, California is graying, as baby boomers retire. The long decline in birth rates, meanwhile, means fewer young adults will enter the workforce over the next 10 to 20 years, Johnson said, and the number of middle-aged workers has remained fairly flat. The state has long relied on immigrants, both authorized and undocumented, to fill those gaps. Losing some of that workforce could have a significant effect.
Trump’s policies could certainly provoke a human crisis. A loss of part of California’s existing migrant community, and the likely discouragement of others from entering the state, could also tamp down its population level.
Ending birthright citizenship, a right guaranteed under the Fourteenth Amendment to the U.S. Constitution, could create chaos on a national scale, not just in California. And while Trump himself has not spoken much of including a citizenship question in census data, it’s something he threatened during his first term before the U.S. Supreme Court rejected it — and it is the subject of a bill that has already been introduced in Congress. For as long as it has been conducted, U.S. Census totals have included all persons, not merely those with citizenship. The new bill would change that.
There are short-term consequences to all of this. As noted by UCLA’s Latino Policy & Politics Institute, Trump’s executive order on birthright citizenship, even if it does not survive legal challenge, is likely in the interim to discourage immigrant families from seeking to satisfy such basic needs as health care, for fear that their status would somehow become known. Likewise, researchers say, if a citizenship question is included in the U.S. Census, fewer immigrants are likely to participate, and their true representation in the population could be obscured as a result.
“Is there a chilling effect? I think certainly there is, yes,” Johnson said. We’re still in the early stages of learning how far Trump wants to push his immigration policies — and what the ultimate cost will be.
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