Population Growth Down Sharply and Projected to Fall Further
Recently released Census data show that population growth slowed sharply in 2025 amid an abrupt decline in immigration. The Census Bureau projects that immigration will decline further in 2026, which would result in historically low growth if natural change (births minus deaths) remains near current levels. Examining how past gains in immigration have contributed to state population growth offers insight into how a future decline would be felt across the country. States that have had more robust domestic migration will be better situated to sustain their growth, while those that haven’t are at greater risk of population loss in the near future.
The recent decline in immigration is undercutting a major source of population growth. The population grew by 1.8 million people in 2025, according to the Population Estimates Program (PEP), down from 3.2 million in 2024. This slowdown was driven entirely by the drop in net international migration, as natural change was essentially flat. The Census Bureau projects that immigration will fall to 321,000 people in 2026. This projected level of immigration is even lower than the Census Bureau’s earlier "low immigration" projection scenario of 389,000 net international migrants in 2026 (Figure 1). In that earlier low scenario, total population growth in 2026 was 980,000—already lower than average annual growth in any decade since the 1930s. Taken together, if the new immigration projection holds and natural change remains near current levels, total population growth in 2026 is likely to be historically low.
Figure 1: Population Growth Down and Poised to Fall Further
Notes: Population estimates are July-to-July. For 2026, immigration is shown only as projections: two scenarios from the Census Bureau’s 2023 projections and the projection released with the 2025 population estimates.
Sources: JCHS tabulations of US Census Bureau, Vintages 2020 and 2025 Population Estimates Program; US Census Bureau, 2023 Population Projections; US Census Bureau. “New Population Estimates Show Historic Decline in Net International Migration.”
The effects of declining immigration will not be felt evenly across states. Over the past five years, immigration has contributed to state population growth to varying degrees (Figure 2). While immigration was positive in every state, it was not large enough to offset overall population loss in 7 states. In 14 states, immigration prevented aggregate population loss from 2021–2025, and in another 12 states, immigration accounted for more than half of all growth. Most states, then, have relied on immigration either to drive recent population gains or to limit the extent of population loss, and will feel the impact of the recent and projected declines.
Figure 2: Many States Rely on Immigration for Population Growth
Many states in the Sunbelt and Mountain West will be better positioned to sustain population growth by relying on domestic migration and natural change. States in these regions with strong net domestic inflows—such as Montana, Idaho, and South Carolina—have relied much less on immigration for recent growth. Idaho, for example, gained 131,000 people from net domestic migration in the past five years, far outpacing gains of 27,000 from natural change and 24,000 from immigration. These states are therefore less vulnerable to a slowdown in immigration.
States that are most reliant on immigration are concentrated in the Northeast, Midwest, and Pacific Northwest. Massachusetts, for example, gained 286,000 people from immigration between 2021 and 2025, far outpacing its gain of 32,000 people from natural change and offsetting its loss of 145,000 people from net domestic outflows. Under a simple scenario where immigration in these states falls at the same rate as the national projection (a 75 percent decline), their population growth would likely slow sharply or even shift to population loss. That outcome could be avoided if net domestic migration or natural change increase, and recent data suggest that regional migration is beginning to shift in favor of "Snow Belt" states, especially in the Midwest.
Immigration drove national population growth in recent years as natural change only slightly recovered from its pandemic-era lows. Given the aging population and the declining birth rate, natural change is expected to decline in coming years, which would compound the effects of declining immigration. At the state level, domestic migration and natural change will become more central to population growth in 2026. Many states—especially in the Sunbelt and Mountain West—will be able to rely on these factors to sustain growth, but states that have depended heavily on immigration in recent years may soon face the prospect of population loss.
