Repeated attacks by the Trump administration against California's immigrant communities over the past year have resulted in thousands of deportations and fueled fear of reprisals among those living in the state without authorization, including families worried about their children. It remains unclear how many immigrants will ultimately leave the state, whether under threat or by choice.
That represents a humanitarian nightmare, says a professor at California Lutheran University. But there is another aspect that must be considered, he adds: California's economy simply cannot survive a significant loss of its undocumented working population.
"Even for people and politicians without any humanitarian instinct, they have to understand the economic punishment that is taking place," said Jamshid Damooei, director of the Center for Economics of Social Issues at the university. "You cannot imagine certain industries in California without undocumented workers." For years, the Cal Lutheran center has tracked the effects of undocumented workers on the state's economy.
Its most recent findings present a compelling argument that those effects are profoundly positive. Damooei said the center's research found that the direct value of work produced by undocumented Californians represents nearly 6% of the state's total gross domestic product, more than $236 billion annually.
But the figure rises when indirect and induced spending is included—ways economists measure how much additional economic activity and spending undocumented immigrants' work generates, essentially a multiplier effect. "The best way to understand it is to think about what undocumented immigrants' work generates for others," Damooei said.
"That is true whether through their work driving more business spending or hiring, supply chain purchases, or the workers' own spending on their needs and tax payments, among other things." Adding those factors, undocumented immigrants are responsible for nearly $441 billion in economic impact—more than 11% of California's GDP. These are striking numbers, though perhaps not surprising given the size of the undocumented workforce in the Golden State.
The center's research puts that figure at more than 1.9 million people, within a total undocumented immigrant population of between 2.5 and 2.9 million. If the term "undocumented worker" evokes the image of a person bent over working in an agricultural field, that is not wrong.
Nearly half of all agricultural jobs in the state are held by immigrant workers, Damooei said; and in places like Santa Barbara and Ventura counties, the figure approaches 70%. But that image, while powerful, is incomplete.
Using information from IMPLAN, the industry standard for economic modeling, Damooei's work demonstrates solidly that immigrant labor sustains multiple industries across the state. Undocumented workers account for nearly half of what the agricultural industry contributes to California's GDP, but also 22% of the construction contribution, 20% of retail trade, and more than 10% of wholesale trade, according to Damooei's research.
Manufacturing, transportation, and warehousing rely heavily on undocumented immigrant labor. In concrete dollars, the figures are even more impressive.
Undocumented workers contribute $37 billion a year to the construction industry in California, $42 billion to retail trade, $29 billion in professional services, and $23 billion in agriculture, among other sectors. This is a nearly invisible workforce that generates very tangible results.
The question of how much these workers pay in taxes is complex, Damooei said, but the amount is considerable. While many immigrants set up individual taxpayer identification numbers to pay taxes, others use fake Social Security numbers or false IDs on W-2 forms, which Damooei called "identity borrowing." Both the federal and California governments accept those tax payments.
A 2024 study by the Institute on Taxation and Economic Policy estimated that total taxes paid by undocumented immigrants in the United States amount to nearly $100 billion. Approximately 16% of those immigrants live in California.
That fiscal aspect of the conversation is often lost amid debates over immigration status, Damooei said, but it is important. Much of the tax money paid by undocumented workers helps sustain the same services supported by the taxes of other Americans: Social Security, Medicare, unemployment insurance, and others.
But because of their immigration status, those workers and their families cannot access those government services. In essence, workers' taxes help sustain social safety net systems they themselves cannot use.
Even in California, a clearly progressive state, Governor Gavin Newsom decided to reverse an expansion of Medi-Cal benefits for undocumented residents, citing budget constraints. "The bottom line is that undocumented people pay much more in taxes than they receive in benefits," Damoeei said.
That dynamic will continue in California for a long time. Cal Lutheran's research shows that, of the high estimate of 2.9 million undocumented residents in the state, 1.7 million have lived here for 20 years or more.
They represent a stable part of the state's workforce. President Donald Trump's attacks on immigrants, and the ICE raids that have shaken the country since early 2025, may appeal to some of Trump's more xenophobic supporters.
But in practice, expelling undocumented people from California would not only be cruel: it would be a recipe for economic disaster, Damoeei said. "These workers are an inseparable part of California's economy.
That's how decisive the impacts are," the professor said. "This is what we are—and who we are—as a society."