The estimated population of unauthorized immigrants in the U.S. stands at around ** million people. Although the number has stabilized, the United States has seen a spike in migrant encounters in the last few years, with over * million cases registered by the U.S. Border Patrol in 2023. This is a slight decrease from the previous year, when there were over *** million cases registered. Due to its proximity and shared border, Mexico remains the leading country of origin for most undocumented immigrants in the U.S., with California and Texas being home to the majority.

Immigration and political division

Despite the majority of the population having immigrant roots, the topic of immigration in the U.S. remains one of the country’s longest-standing political debates. Support among Republicans for restrictive immigration has grown alongside Democratic support for open immigration. This growing divide has deepened the polarization between the two major political parties, stifling constructive dialogue and impeding meaningful reform efforts and as a result, has led to dissatisfaction from all sides. In addition to general immigration policy, feelings toward illegal immigration in the U.S. also vary widely. For some, it's seen as a significant threat to national security, cultural identity, and economic stability. This perspective often aligns with support for stringent measures like Trump's proposed border wall and increased enforcement efforts. On the other hand, there are those who are more sympathetic toward undocumented immigrants, as demonstrated by support for the Deferred Action for Childhood Arrivals (DACA) program.

In January 2022, it was estimated that about 1.85 million male illegal immigrants living in the United States were aged between 35 and 44 years old. In that same year, it was estimated that 1.52 million female illegal immigrants living in the U.S. were between 35 and 44 years old.

In 2022, an estimated 10.99 million unauthorized immigrants were living in the United States. This is an increase from about 3.5 million unauthorized immigrants who lived in the United States in 1990.

This study was conducted to examine whether a rising crime rate in El Paso, Texas and San Diego, California in 1986 could be attributed to, among other factors, the influx of undocumented aliens. Variables include level of involvement of undocumented aliens in serious felony arrests in San Diego and El Paso Counties, the outcome of serious felony arrest cases involving undocumented persons compared to others arrested for similar offenses, the impact of arrests of undocumented aliens on the criminal justice system in terms of workload and cost, the extent that criminal justice agencies coordinate their efforts to apprehend and process undocumented aliens who have committed serious crimes in San Diego and El Paso counties, and how differences in agency objectives impede or enhance coordination. Data are also provided on how many undocumented persons were arrested/convicted for repeat offense in these counties and which type of policies or procedures could be implemented in criminal justice agencies to address the issue of crimes committed by undocumented aliens. Data were collected in the two cities with focus on serious felony offenses. The collection includes sociodemographic characteristics, citizenship status, current arrest, case disposition, and prior criminal history with additional data from San Diego to compute the costs involving undocumented aliens.

In 2022, the greatest number of illegal aliens returned in the United States were from the Philippines, with ****** illegal aliens returned. India, Canada, China, and Russia rounded out the top five in that year.

In 2019, California had the highest population of unauthorized immigrants, at around **** million. The overall figure for the United States was estimated to be around ***** million unauthorized immigrants.

As of January 2022, it was estimated that about 4.81 million illegal immigrants from Mexico were living in the United States. It was also estimated that 750,000 illegal immigrants from Guatemala were living in the United States.

Thailand Number of Aliens Work Permit: Pg: Illegal Immigrants data was reported at 4,705.000 Unit in Dec 2017. This records an increase from the previous number of 4,347.000 Unit for Nov 2017. Thailand Number of Aliens Work Permit: Pg: Illegal Immigrants data is updated monthly, averaging 4,461.000 Unit from Jan 2014 (Median) to Dec 2017, with 48 observations. The data reached an all-time high of 13,608.000 Unit in Mar 2017 and a record low of 2,460.000 Unit in Jan 2014. Thailand Number of Aliens Work Permit: Pg: Illegal Immigrants data remains active status in CEIC and is reported by Department of Employment. The data is categorized under Global Database’s Thailand – Table TH.G007: No of Aliens Work Permit.

Acknowledgement

The following table is imported from the 2019 Yearbook of Immigration Statistics under the Department of Homeland Security:

The 2019 Yearbook of Immigration Statistics is a compendium of tables that provide data on foreign nationals who are granted lawful permanent residence (i.e., immigrants who receive a “green card”), admitted as temporary nonimmigrants, granted asylum or refugee status, or are naturalized. The Yearbook also presents data on immigration enforcement actions, including apprehensions and arrests, removals, and returns.

Table 39. Aliens Removed or Returned: Fiscal Years 1892 to 2019 (https://www.dhs.gov/immigration-statistics/yearbook/2019/table39)

Inspiration

The data was collected to observe trends in history reflecting the number of immigrants deported - more specifically removed or returned.

The provided data includes: year, tonnage, fisheries products, agricultural products, tobacco, alcohol, drugs, firearms, smuggling, others, subtotal, cancellations, fines, and other field data.

This statistic shows the estimated GDP loss if all illegal immigrant workers were removed from the United States. As of September 2016, the manufacturing industry would suffer an estimated 74 billion U.S. dollar decline in GDP output if all illegal immigrant workers were removed from the U.S.

Thailand Number of Aliens Work Permit: Illegal Immigrant data was reported at 66,483.000 Unit in Oct 2018. This records an increase from the previous number of 65,125.000 Unit for Sep 2018. Thailand Number of Aliens Work Permit: Illegal Immigrant data is updated monthly, averaging 25,261.000 Unit from Jan 1994 (Median) to Oct 2018, with 298 observations. The data reached an all-time high of 206,014.000 Unit in Nov 1997 and a record low of 4,557.000 Unit in Nov 1996. Thailand Number of Aliens Work Permit: Illegal Immigrant data remains active status in CEIC and is reported by Office of Foreign Workers Administration (Work Permit). The data is categorized under Global Database’s Thailand – Table TH.G007: No of Aliens Work Permit.

Graph and download economic data for Employment Level - Foreign Born (LNU02073395) from Jan 2007 to Jun 2025 about foreign, household survey, employment, and USA.

According to the source, ***** irregular migrants arrived in Spain in January 2021, which represented the highest number of irregular migrants of the study period, second only to October 2018, with ***** cases. February, March and April tend to be the months with the lowest arrival of illegal migrants.