Immigration Has Fueled Growth Across Wealthy Nations for Decades, Study Concludes

immigration has delivered substantial economic gains to wealthy countries over the past three decades, boosting long-term economic growth, according to new research that analyzed dozens of advanced economies within the Organisation for Economic Co-operation and Development (OECD).

The study, which will be presented next week at the European Central Bank’s annual Forum on Central Banking in Sintra, Portugal, concludes that countries experiencing higher levels of immigration consistently saw stronger gains in labor productivity and gross domestic product (GDP) per worker.

Researchers analyzed migration and economic data from OECD member countries between 1990 and 2024. During that period, the number of immigrants living in OECD nations who were born outside the bloc increased dramatically, rising from roughly 25 million to about 100 million people.

The paper saw that a rise in immigration equivalent to 1% of a country’s population was associated with a 1.2% increase in GDP per worker within five years and a 1.9% increase after a decade. The authors found that much of this productivity improvement stemmed from higher levels of business investment that accompanied growing labor forces.

The findings are particularly relevant as many advanced economies confront shrinking working-age populations due to aging demographics and declining birth rates. Several European countries have experienced negative natural population growth for years, increasing reliance on immigration to sustain labor markets and economic activity.

The study highlights Spain, Italy, and the United Kingdom as examples where immigration appears to have made a substantial contribution to productivity growth. In Spain, the immigrant share of the adult population increased by approximately 15 percentage points between 1990 and 2024.

Researchers estimate that this influx may have contributed to nearly 28% higher GDP per worker growth during that period. Since Spain’s actual GDP per worker rose about 75%, immigration could account for roughly one-third of those gains.

The United Kingdom experienced a similar pattern. Immigration increased by about 10 percentage points as a share of the population, with researchers estimating that nearly one-fifth of the country’s overall productivity growth over the past three decades can be attributed to immigration.

One of the study’s most notable conclusions is that the economic benefits do not appear to diminish as immigrant populations grow. Researchers pointed to countries such as Canada and Australia, which have among the highest shares of foreign-born residents in the developed world.

Their experience suggests that advanced economies can continue absorbing immigrants while maintaining positive effects on investment, innovation, and productivity. The authors also note that many recent immigrants to OECD countries have been highly educated or possess skills that complement domestic labor markets, helping businesses expand production and encouraging companies to invest in new equipment, technology, and facilities.