How Many Illegals are in the U.S.?

According to a government report, 10.5 million unauthorized immigrants were living in the U.S. in 2005, up from 8.5 million in 2000—a 24 percent increase. Fifty-seven percent are from Mexico, followed by much smaller numbers from El Salvador (4 percent), Guatemala (4 percent), India (3 percent), China (2 percent), and other countries.

These figures come from the Department of Homeland Security. They were calculated using the "residual method" of population estimation. Researchers in the Office of Immigration Statistics subtracted the number of legal foreign-born residents (based on administrative data at the Department of Homeland Security) from the total number of foreign-born (based on estimates from the Census Bureau's American Community Survey), and the difference—or residual—is the number of illegals in the U.S.

The number of unauthorized immigrants is growing by 408,000 per year, according to the report.

Not surprisingly, California is home to the largest number of unauthorized immigrants—2.8 million or 26 percent of the total in 2005. Other states in the top five are Texas (1.4 million), Florida (850,000), New York (560,000), and Illinois (520,000). But the number of illegals is growing the fastest in Georgia, where it has more than doubled between 2000 and 2005—climbing from 220,000 to 470,000 between 2000 and 2005.