This report presents estimates of the US undocumented population for 2017 derived by the Center for Migration Studies of New York (CMS). It focuses on the steep decline in the undocumented population from Mexico since 2010. While the president has focused the nation’s attention on the border wall, half a million US undocumented residents from Mexico left the undocumented population in 2016 alone, more than three times the number that arrived that year, leading to an overall decrease of nearly 400,000 undocumented residents from Mexico from 2016 to 2017. From 2010 to 2017, the undocumented population from Mexico fell by a remarkable 1.3 million.
For the past 10 years, the primary mode of entry to the undocumented population has been to overstay temporary visas. This report provides estimates of the number of noncitizens who overstayed temporary visas and those who entered without inspection (EWIs) in 2016 by the top five countries of origin.