Short answer: In most advanced economies—especially the United States—halting new immigration would likely create or worsen labor shortages in several sectors, though the size of the effect depends on the business cycle, demographics, and how fast employers and policymakers adapt.
Why stopping immigration tends to tighten labor markets
•Demographics: With aging populations and low fertility, recent immigrants are a major source of labor‑force growth. Turning that off shrinks the pipeline of working‑age people just as retirements rise, pushing vacancies up.
•Sector exposure: Jobs with high immigrant shares—agriculture and food processing, construction, hospitality, janitorial services, trucking and delivery, childcare, home health and eldercare, and parts of healthcare and STEM research—would feel the pinch first.
•Geography: Regions and metro areas that rely more on immigrant workers would see sharper shortages and service cutbacks.
•Price and wage effects: Employers would raise pay and improve conditions to attract domestic workers, but some roles remain hard to fill due to hours, location, or physical demands. Expect higher consumer prices in labor‑intensive services (food, caregiving, hospitality) and possible delays or reduced capacity.
How the economy might adjust
•Substitution: More automation, self‑service, and process redesign; some production may shift overseas; firms may scale back offerings that can’t be automated or offshored.
•Participation: Policies that expand childcare, reform licensing, support training/apprenticeships, and enable older or formerly incarcerated workers can help—but take time and budget.
•Productivity: Investment can offset part of the worker shortfall, but typically not fast enough to prevent near‑term shortages in hands‑on services like caregiving.
When shortages might be smaller
•In a recession or slack labor market, fewer immediate shortages—but skill and location mismatches can still leave certain occupations short.
•If “stopping immigration” means only a modest reduction rather than a near‑zero inflow, the effects scale down accordingly.
Bottom line: Completely stopping new immigration would almost certainly tighten the labor market and produce acute shortages in immigrant‑heavy occupations, raise costs for consumers, and slow overall growth unless offset by significant, sustained gains in domestic labor participation and productivity.
If you can share the country you have in mind, the time horizon (e.g., next 2–5 years vs. decades), and whether you mean a total halt or a large reduction, I can give a more tailored estimate.