The United States and Canada are well below the replacement fertility threshold of 2.1 children per woman with no foreseeable reversal, and it is now net migration that sustains demographic growth on the continent. This shift transforms immigration from a matter of societal choice into a structural adjustment variable. The question is no longer whether North America depends on migration flows, but whether it has the means to assume this dependency.
The Essentials
- North American fertility has fallen below the replacement threshold of 2.1, making net migration indispensable for maintaining the working-age population.
- Natural increase in the United States is approximately 519,000 people in 2025; total continental growth (natural and migratory combined) is approximately 4 million people, while net migration in the United States alone was 1.3 to 2.8 million depending on the year, and approximately 990,000 for all of North America (broad definition) in 2025 according to Countrymeters (Worldometer / UN DESA, 2024 revision).
- Canada has explicitly built its growth model on announced migration targets and equipped integration systems; the United States manages the same dependency without assuming it politically.
- Sustained migration restriction, under electoral pressure, would accelerate demographic decline with direct consequences for pensions and available labor supply.
- The tension between structural necessity and political resistance is the primary risk to North American demographic sustainability over the next thirty years.
Below-Replacement Fertility Has Become the Norm, Not the Exception
American fertility ended 2023 at 1.621 children per woman according to the Centers for Disease Control and Prevention, a modern record low, which 2024 has already surpassed with a rate falling to 1.599. The general fertility rate for 2023 was the lowest in more than a century, not merely since records began. Canada shows fertility of 1.26 in 2023 and 1.25 in 2024, according to Statistics Canada, an absolute record, well below previous estimates. These two countries are joining a trend now affecting nearly all developed economies, from South Korea to Japan to much of Southern Europe.
What distinguishes the North American situation is the speed at which this shift has occurred. In the United States, fertility had still barely reached the replacement threshold in the early 2000s, partly sustained by higher fertility among immigrant and Hispanic populations. This buffer has eroded: women from these groups adopted reproductive behaviors comparable to the rest of the population within a single generation. The biological engine of American demographic growth has stalled without any public policy managing to maintain it.
The reasons for this decline are documented and convergent: housing costs in major metropolitan areas, duration and cost of education, delayed couple formation, economic uncertainty felt by young adults. These structural factors explain why none of the affected countries has succeeded in durably reversing a downward trend through measures supporting natality, however generous. Viktor Orbán’s Hungary spent considerable sums trying to boost its fertility: the result remains disappointing.
Migration Does the Work That Natality No Longer Does
2025 data from Worldometer and the UN Department of Economic and Social Affairs’ 2024 revision allow us to measure the gap. Natural increase in the United States stands at approximately 519,000 people per year according to the US Census Bureau; total growth on the North American continent, natural and migratory combined, is approximately 4 million people. Net migration in the United States alone was 1.3 to 2.8 million depending on the year; for all of North America (broad definition), it stands at approximately 990,000 in 2025 according to Countrymeters. These proportions are misleading at first glance: natural increase remains positive, so the situation does not yet resemble that of Japan or Germany in the 2000s.
But trajectory matters more than level. Natural increase mechanically declines as baby-boom cohorts age and births no longer offset deaths. According to UN projections (World Population Prospects 2024), American fertility rates should remain approximately stable through the end of the century, with no return to the replacement threshold. Migration is not a complement: it becomes progressively the sole mechanism of growth.
This arithmetic reality has concrete consequences for labor markets and pension systems. The dependency ratio—the number of working-age people per retiree—deteriorates as baby boomers exit employment and subsequent generations are smaller in number. In the United States, the Social Security Administration projects that its reserves will be depleted by the mid-2030s without adjustment, under the combined effect of increasing longevity and the relative contraction of the contribution base. Immigration of working-age workers is one of the few levers that acts simultaneously on both sides of the balance.
Canada Has Transformed Necessity Into Strategy
The difference between Canada and the United States on this issue stems less from demography itself than from how each country has chosen to govern its migration dependency. Ottawa acknowledged the situation several decades ago and constructed an explicit framework: publicly announced annual targets (around 500,000 new permanent residents per year since 2023), a selection system based on skills and labor market needs, and investments in welcoming and integrating arrivals.
The Canadian points system, known as Express Entry, selects immigration candidates based on their education level, professional experience, mastery of official languages, and pre-existing connections to the Canadian labor market. It has been criticized for difficulty in recognizing foreign credentials and delays in effective integration into regulated professions. It nonetheless represents a form of assumed governance, where migration dependency is explicitly managed rather than endured.
Results are measurable. Canadian demographic growth has been among the fastest in the G7 in recent years, driven approximately 80% by net migration according to Statistics Canada. This growth fuels domestic consumption, maintains the tax base, and delays painful adjustments to social protection systems. It also creates pressure on housing and public services in major metropolitan areas, pressures that the federal government was slow to anticipate. Ottawa indeed announced in late 2023 a temporary downward adjustment to its targets, under the effect of housing market tension, a sign that even the most explicit model remains vulnerable to second-order effects.
The United States Manages the Same Dependency Without Naming It
The United States is in a structurally identical position to Canada, but it does not assume it in the same terms. The country welcomes several hundred thousand legal permanent immigrants each year, to which must be added flows of temporary workers, asylum seekers, and an undocumented population estimated at 14 million people in 2023 according to the latest Pew Research Center estimate published in August 2025, a historical record. These flows have sustained American demographic growth at a level that fertility alone would not have permitted.
But American migration policy has been conceived, over decades, around family categories rather than economic ones. The preferential visa system grants substantial weight to family ties, which produces demographically useful results but is less directly calibrated to labor market needs. Attempts to reform toward a points system comparable to the Canadian model have systematically failed in Congress, victims of partisan blockages.
The rise of anti-immigration rhetoric since the 2016 presidential campaign, and especially since 2024, has introduced a new variable: American migration policy now oscillates between a discourse presenting immigration as a threat to employment and national cohesion, and an economy that continues to absorb millions of foreign workers because local labor supply is not available in sufficient quantities in rapidly growing sectors, from construction to health to agriculture. This gap between narrative and reality constitutes a major political fragility.
What Awaits the Continent If Restriction Prevails
The prospective dimension of this question deserves to be posed without dramatization, but with precision. Two trajectories are plausible by horizon 2050, and current signals allow us to distinguish between them.
In the first scenario, North American countries progressively make explicit their migration dependency and invest in the systems that make it productive. This requires better-funded integration policies, faster recognition of foreign qualifications, facilitated access to housing in host cities, and public pedagogy linking immigration to pension sustainability. Canada has begun this path; the United States has considered it several times without taking it. In this scenario, demographic growth remains sufficient to maintain a viable contribution base and finance intergenerational transfers. Pressure on public services is real but manageable if investment follows.
In the second scenario, migration restriction prevails durably, under the effect of electoral pressure that supersedes structural necessities. This shift is not hypothetical: American politics since 2025 has shown that a determined administration can significantly reduce legal and illegal flows within a matter of months. If this orientation extends over a decade, the migration balance shrinks, and demographic growth then depends almost entirely on insufficient natural increase. Working-age population aging accelerates. The dependency ratio deteriorates.
Pension systems must choose between three equally painful solutions: increase contributions, reduce benefits, or raise the retirement age. Allowing adjustment to occur by default remains an option, but rarely the least costly.
Economists actively debate automation’s capacity to partially compensate for contraction in the human workforce. Daron Acemoglu and Simon Johnson have shown in their recent work that technology generates collective gains only when it increases worker productivity rather than replacing them. AI agents deployed in American companies could theoretically ease pressure on available labor, but this mechanism remains conditional on a technological orientation that is not guaranteed. Automation does not finance pensions: only contributing workers do.
Migration Policy as a Short-Term Civilizational Choice
François Lenglet, in his analysis of French and Western economic dynamics, emphasizes the distinction between adjustments that can wait and those that cannot. Demography belongs to the second category: decisions made today on migration flows and integration systems will produce their effects on labor markets in the 2030s and 2040s, with a transmission delay that leaves little room for correction.
This reading enters into tension with that of researchers more cautious about the net economic effects of large-scale immigration. George Borjas, economist at Harvard, has produced work showing that massive immigration exerts downward pressure on wages of native unskilled workers. This argument is serious and should not be dismissed. It concerns the distribution of gains, not their existence. Immigration creates aggregate economic value in the great majority of available studies; the central question concerns the distribution of this value and the redistribution policies that accompany flows.
Canada has attempted to address this tension by preferentially selecting skilled immigrants, thus reducing pressure on the most vulnerable segments of the labor market. The United States, with a system more based on family reunification, exposes unskilled workers more to this competition. Neither model is without cost. But Canada has at least chosen its trade-off explicitly, which makes it possible to evaluate its results and adjust course.
This is precisely the capacity for adjustment that is lacking in American debate. When migration policy becomes an identity signal rather than an instrument of demographic management, it loses its capacity to adapt to real needs. The signals to follow in the coming years are readable: the evolution of the dependency ratio, recruitment tensions in health and care sectors, the trajectory of Social Security reserves. These indicators will signal well before official projections whether North America chooses to govern its migration dependency or to endure it.
Canadian experience, with its limitations and ongoing corrections, shows that a society can build durable consensus around immigration when it explains the reasons and invests in reception conditions. The recomposition of labor markets that automation is beginning to produce adds another layer of complexity: the occupations for which migration need will be strongest in twenty years are not necessarily those under tension today. Anticipating this evolution will require training and integration systems capable of continuous adaptation, not fixed quotas.
The question each country must settle, in its own way, is this: are they prepared to construct the institutions that make migration dependency viable long-term, or do they prefer to maintain it in silence, exposed at each electoral cycle to a reversal that no demographic arithmetic can absorb without damage?
Sources
- Worldometer / UN DESA, North America Demographic Data 2025
- Centers for Disease Control and Prevention, National Vital Statistics Reports (US fertility data 2023)
- Statistics Canada, Population and Migration Estimates, 2023-2024
- Pew Research Center, Estimates of Undocumented Population in the United States
- UN DESA, World Population Prospects, 2024 revision
- Social Security Administration, 2024 Trustees Report (reserve projections)
- Daron Acemoglu and Simon Johnson, Power and Progress (2023), Basic Books
- CDC/NCHS, Births: Final Data for 2023 (TFR = 1.621)
- Statistics Canada, Fertility and Baby Names 2024 (TFR = 1.25)
- SSA Trustees Report Summary 2026 (OASI depletion 2032, combined 2034)
- Pew Research Center, Unauthorized Immigrants 14M in 2023
- US Census Bureau, Vintage 2025 (natural increase ~519,000)
- Canada.ca, Immigration Plan 2023-2025 (target 465,000 in 2023, 500,000 in 2025)
- Canada.ca, Express Entry (official system)
- Statistics Canada, Canada Tops G7 Growth (G7 growth)
- CDC/NCHS – Births Final Data 2023 (NVSR Vol. 74 No. 1)
- CDC/NCHS – Data Brief 535 (Births Final Data 2024, July 2025)
- Statistics Canada – Births and Stillbirths 2023 (The Daily, Sept. 2024)
- Statistics Canada – Fertility and Baby Names 2024 (The Daily, Sept. 2025)
- US Census Bureau – Vintage 2025 Population Estimates (Jan. 2026)
- SSA – 2026 Annual Trustees Report (official release, June 2026)
- IRCC Canada – Immigration Levels Plan 2023-2025 (Nov. 2022)
- Pew Research Center – Unauthorized Immigrants USA 2023 (August 2025)
- Pew Research Center / UN – Fertility Trends 2025 (August 2025)