People with luggage arrive at Terminal 4 of the Heathrow International Airport, a day after a fire at a nearby electrical substation wiped out the power at the airport, near London, Britain, March 22, 2025. Image @ REUTERS/Isabel Infantes
As far-right parties across Europe and North America sharpen their anti-immigration rhetoric, a sweeping new study set to be presented at one of the world’s most prestigious central banking forums delivers a starkly different verdict: mass immigration has been an economic engine, not a burden.
The research, authored by University of California, Davis professor Giovanni Peri, draws on data from dozens of wealthy nations in the Organisation for Economic Co-operation and Development spanning more than three decades. It finds that countries which absorbed the highest volumes of immigrants since 1990 recorded the strongest gains in growth and productivity, and that many could still take in more workers without losing those benefits.
“Receiving countries’ labour productivity grew significantly during and after periods of higher immigration rates,” the paper states. “The predictive coefficients are often significant, economically large and a significant portion of such growth in GDP per worker is realized through strong growth in investments.”
The study will be presented at the ECB Forum on Central Banking in Sintra, Portugal, next week, a high-profile platform that gives the findings considerable weight in policy circles.
At the heart of the research is a striking statistical relationship: every increase in immigrants equivalent to 1% of a country’s population is associated with GDP-per-worker growth of 1.2% within five years, rising to 1.9% over a decade. The total number of immigrants arriving in OECD countries from outside the bloc surged to roughly 100 million in 2024, up from about 25 million in 1990, a period during which native population growth turned negative across many member states.
The implications are particularly pointed for the European Union, where natural population change has been negative since 2015, a trend that deepened following the COVID-19 pandemic. In Spain, the immigrant share of the adult population rose by 15 percentage points between 1990 and 2024, a shift the paper links to a potential 28% boost in GDP-per-worker growth. Spain’s actual GDP per worker grew by around 75% over the same period, suggesting immigration may account for as much as one third of that gain.
Britain presents a similar picture. With immigrants rising by 10 percentage points as a share of the total population, the study estimates they contributed roughly 19% of GDP-per-person growth out of a total increase of 60%. Italy is also cited alongside Spain and the UK as a country where up to a third of economic growth per worker may trace back to immigration inflows over the 35-year window.
Crucially, the research finds that the productivity dividend from immigration does not diminish as inflows grow larger. The experiences of Canada and Australia, both countries with substantially foreign-born populations and well-established managed migration programmes, suggest that receiving nations retain significant capacity to absorb additional workers without eroding the gains in productivity or investment.
The findings land at a charged political moment. Anti-immigration sentiment has propelled far-right parties to electoral gains in the United States, Germany and Britain, pushing migration controls to the top of legislative agendas. Yet Peri’s research, which focuses specifically on highly skilled immigrants who make up the majority of OECD inflows, challenges the foundational premise of that backlash, that immigration depresses wages, strains public services and slows growth.
The paper does not dismiss the complexity of migration’s social and fiscal dimensions, but its core economic argument is unambiguous: for wealthy nations navigating ageing populations and slowing labour force growth, immigration has been among the most consequential drivers of prosperity over the past generation.
By: Andrews Kwesi Yeboah