As the 2030 Census approaches, the U.S. Census Bureau’s 2025 vintage estimates showed that Massachusetts’s population growth has slowed in the last year, in large part due to a decrease in international immigration.
At a Senate Committee on the Census hearing on Tuesday, Feb. 10, Susan Strate, senior manager at the UMass Donahue Institute Population Estimates Program, said that following a year of the largest population increase in 60 years, Massachusetts’s population increased by just 15,524 people from April 1, 2024 to July 1, 2025, a rate of 0.2%.
It’s not uncommon for Massachusetts to have slower population growth compared to the nation. But as preparations for the next census continue, Massachusetts’s population trends could impact congressional representation and state redistricting. In 2010, Massachusetts lost one of its congressional seats after its population grew at a slower rate than other states.
And population trends could impact other areas in the state, like the economy and the elder dependency ratio.
Susan Strate, senior manager at the UMass Donahue Institute Population Estimates Program, speaks to the Senate Committee on the Census on Feb. 10, 2026.
Susan Strate, senior manager at the UMass Donahue Institute Population Estimates Program, speaks to the Senate Committee on the Census on Feb. 10, 2026.
Why is Massachusetts’s population growth slowing?
The biggest contributor to the decline in population growth last year was a decrease in foreign immigration to the state.
Immigrants play a huge role in Massachusetts, which has the sixth highest proportion of foreign-born residents in the country, Strate said. Massachusetts was third in the nation for per capita H1B visas in 2024, and immigrants in the state are more likely to have a graduate degree than native born residents. The foreign-born labor force has increased at a much higher rate than the native-born force, and foreign-born residents are also younger on average than the native-born population.
But as the Trump administration has cracked down on immigration in the U.S., that population has fallen off both in Massachusetts and across the country.
2025 vintage estimates from the Census Bureau show that Massachusetts’s net international migration fell from nearly 80,000 in 2024 to just 40,000 in 2025.
“And remember that this 2025 value is just for the first half of the calendar year for 2025,” Strate said. “There have been more actions since July 1, 2025, which would lead us to believe that the next year immigration estimate will come down even more.”
Other factors that contribute to population change are births, deaths and domestic migration. Strate said that Massachusetts’s birth rate is slightly declining and its death rate is slightly increasing, but that both trends are expected to accelerate in the coming years – especially as 30% of all births in Massachusetts are to foreign-born mothers.
“If you think about how fertility will also be undermined, thinking back to percent of births by foreign-born people in Massachusetts, you are kind of looking at a convergence of factors that will really undermine our population,” she said.
Domestic migration is another factor: Census data released Jan. 27 found that Massachusetts experienced a net loss of 33,340 people to other states between July 1, 2024 and July 1, 2025.