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How many immigrants are in the United States illegally?
Unauthorized Immigration in the United States
Current Estimates
The most reliable estimates suggest there are approximately 10-12 million unauthorized immigrants currently living in the United States. However, this number comes with important caveats about measurement challenges and data limitations.
Key Data Sources and Estimates
Government and Research Institution Estimates:
- Pew Research Center (2021): Approximately 10.5 million unauthorized immigrants
- Department of Homeland Security (2018): Estimated 11.4 million (most recent official estimate)
- Migration Policy Institute: Similar range of 10-12 million
Historical Context:
- Peak: Around 12.2 million in 2007
- Trend: The population has remained relatively stable or slightly declined since the 2008 recession
- 1990s-2000s: Saw significant growth in this population
Measurement Challenges
Why Exact Numbers Are Difficult to Determine:
- Hidden Population: Many individuals avoid government contact
- Survey Limitations: Standard surveys may miss or undercount this population
- Dynamic Status: People’s legal status can change over time
- Mixed-Status Families: Households often include both authorized and unauthorized members
Methodological Approaches:
- Residual Method: Subtracting estimated legal immigrants from total foreign-born population
- Survey Data: American Community Survey and Current Population Survey
- Administrative Records: Various government databases
Geographic and Demographic Patterns
Top States by Population:
- California
- Texas
- Florida
- New York
- New Jersey
- Illinois
Countries of Origin:
- Mexico (historically the largest source)
- El Salvador
- Guatemala
- Honduras
- China
- India
Important Considerations
Legal Complexity:
- Some individuals may be in legal limbo or have pending cases
- Various temporary statuses exist (TPS, DACA, etc.)
- Entry methods vary (visa overstays vs. border crossings)
Data Limitations:
- Estimates typically lag by 2-3 years
- Margins of error can be substantial
- Different methodologies can yield different results
The figure of 10-12 million represents the best available estimate from reputable research organizations and government agencies, though the inherent challenges in measuring unauthorized populations mean this should be understood as an approximation rather than a precise count.