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Illegal immigration

5 questions, with yearly data from 1925 to 2026.

Questions

QuestionYearsTrust
How many immigrants live in the US without legal status, and how has the number changed since 1990?12.2 million unauthorized immigrants living in the US, Each source's latest estimate: January 2022Illegal immigration · United States1990–202658 Low
How many irregular border crossings into the EU are detected each year, and on which routes?179,921 detections of irregular border crossing at the EU's external borders, Calendar year, sum of January–December monthly valuesIllegal immigration · European Union2008–202563 Moderate
How many people are stopped at the US southwest border each year, and how has it changed since 1925?237,538 Border Patrol apprehensions (Title 42 expulsions included 2020-2023) at the southwest border; events, not people, Fiscal year 2025Illegal immigration · United States1925–202563 Moderate
How many people arrive in the UK by small boat, and how many claim asylum?41,472 people detected arriving by small boat, 2025Illegal immigration · United Kingdom2018–202663 Moderate
How many people found staying illegally in European countries are ordered to leave, and how many actually leave?33 countries % returned, of people ordered to leave in the same year (Eurostat)Illegal immigration · Europe2008–202571 Moderate
Who publishes what (2 countries, 4 breakdowns)

Years this site has for each country and breakdown. "Stopped" means the country's figures in the UN homicide file stop after that year while its totals continue (reporting gaps). An empty cell means no source on this site, not that none exists.

CountryPeople by immigration statusPeople by citizenshipPeople by sexPeople by age
GBR–2018–20262018–20262018–2026
USA1990–20261925–2025––
Recorded changes in how sources report (90)
  • 2026, CIS: July 2026 estimate is preliminary because some administrative data were not yet available. source · page
  • 2026, Frontex: Frontex, 19 October 2026: data for the Western Mediterranean land route for 30 and 31 July 2026 "are under review by the respective Member State and are not yet included". source · page
  • 2026, Western Med: Frontex, 19 October 2026: data for the Western Mediterranean land route for 30 and 31 July 2026 "are under review by the respective Member State and are not yet included". source · page
  • 2026, Asy_01c: Classified as "Official Statistics in Development": the methods and data matching "may not yet be fully developed". source · page
  • 2026, Asy_02c: Home Office: "Data for 2026 Q1 onwards is provisional and will be revised in a future publication." source · page
  • 2026, Eurostat: Eurostat notes a break in time series for Denmark in the first quarter of 2026 following a change in methodology (after the last annual figure shown here). source · page
  • 2025, CIS: The January 2025 CPS was the first weighted to the Census Bureau's raised migration estimates; CIS says its 2023 and 2024 estimates "may be too low". source · page
  • 2025, Frontex: Frontex's release of 15 January 2026 gave "almost 178 000" detections for 2025 as preliminary figures; the file of October 2026 sums to 179,921. source · page
  • 2025, All: CBP removed the appointment scheduling function from the CBP One app effective 20 January 2025 and cancelled all existing appointments. source · page
  • 2025, OFO Title 8: CBP removed the appointment scheduling function from the CBP One app effective 20 January 2025 and cancelled all existing appointments. source · page
  • 2025, IER_D01: Home Office: data "for January 2025 onwards for small boat arrivals" were produced using "enhanced data processing and matching methods at the individual record level", which "may result in small differences compared with historical publications"; January 2025 to March 2026 were revised in the August 2026 release. source · page
  • 2025, IER_D01: Nationality, age and sex are taken from the latest information at extraction, not from the first record. Home Office: people deemed stateless "will later have their nationality updated to 'Refugee'" after being granted refugee status (22 arrivals were listed as "Refugee" in 2023, 1,256 in 2025). source · page
  • 2025, IER_D01: Home Office: data "October 2025 onwards for recorded detections in the UK and at UK ports" were produced with enhanced record-level processing; October 2025 to March 2026 were revised in the August 2026 release. source · page
  • 2025, Asy_02c: Home Office user guide, section 2.8: the CID caseworking system "was decommissioned in April 2025"; under its replacement, Atlas, the statistics category for each decision "is no longer available" and the categorisation method was revised. source · page
  • 2025, Eurostat: Eurostat notes a break in time series for Belgium's return data due to a change in the data source from the first quarter of 2025. source · page
  • 2025, Eurostat: Eurostat notes a break in time series for Italy's orders to leave and return data due to a change in the data source from the first quarter of 2025. source · page
  • 2025, Eurostat: Eurostat's 2025 article says only Italy reported all returns as forced returns, so no voluntary departures are counted. source · page
  • 2024, CMS: CMS replaced this series in May 2026 with new estimates (Allen and Warren) that put 2024 at 14.6 million; that figure is a separate line (CMS 2024), never joined to this one. source · page
  • 2024, CMS 2024: New CMS method and series replacing the Warren estimates; earlier years under the new method could not be retrieved. source · page
  • 2023, CBP: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, All: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, All: From January 2023 people without entry documents could book an appointment through the CBP One app to present themselves at certain southwest border ports of entry; OHSS reports that most of the OFO southwest border encounters in FY2023 were of people registered with the app. These are counted as OFO inadmissibles. source · page
  • 2023, USBP Title 8: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, Title 42: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, OFO Title 8: From January 2023 people without entry documents could book an appointment through the CBP One app to present themselves at certain southwest border ports of entry; OHSS reports that most of the OFO southwest border encounters in FY2023 were of people registered with the app. These are counted as OFO inadmissibles. source · page
  • 2023, Mexico: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, Other: Title 42 expulsions ended on 11 May 2023; from then all encounters are processed under Title 8. source · page
  • 2023, Daily series: The Home Office flags 9 days between 2023-02-08 and 2025-09-06 as "Revised" in the daily series. source · page
  • 2023, IER_D02: Home Office: IER_D02 to IER_D05 for "2023 onwards" were produced using enhanced record-level matching; 2023-2025 were revised in May and August 2026, earlier years were not. source · page
  • 2023, IER_D03: Home Office: IER_D02 to IER_D05 for "2023 onwards" were produced using enhanced record-level matching; 2023-2025 were revised in May and August 2026, earlier years were not. source · page
  • 2022, DHS: The 2022 estimate uses ACS data tied to the 2020 Census. Each edition publishes the 10 leading countries of birth. source · page
  • 2022, Pew: The 2022 and 2023 estimates incorporate the Census Bureau's December 2024 revision of international migration; the 2023 report supersedes all earlier Pew estimates. Country of birth is published for every year, with Mexico and "Other than Mexico" in the same table. source · page
  • 2022, CMS: Undercount adjustment raised to 42% for post-2020 arrivals (about 15% before for the newest arrivals). The 2023 article applied it to 2022 and 2023, but printed its revised 2022 figure only in a chart; the 2022 point here is the earlier published 10.94 million. source · page
  • 2022, IER_D01: Home Office: "The 2022 Q3 (July to September) total small boat arrivals figure is sourced from case working systems rather than manual records due to more detailed reporting." source · page
  • 2021, DHS: No estimate for January 2021: the Census Bureau judged the 2020 ACS below its quality standards because of the pandemic. source · page
  • 2021, Eurostat: Regulation (EU) 2020/851 added breakdowns for persons found illegally present (such as reason and place of apprehension); 2021 is the first reference year for the amendments. source · page
  • 2021, IER_D01: From 2021, some small-boat arrivals have no nationality, sex or age recorded yet ("Not currently recorded": 582 in 2021, 877 in 2025). Home Office: "Data, particularly from more recent periods, may have a number of cases where a full breakdown is not yet available." source · page
  • 2021, Eurostat: Regulation (EU) 2020/851, amending Regulation (EC) No 862/2007, applies from reference year 2021: return statistics became quarterly and mandatory for all Member States, with more breakdowns for people found to be illegally present and returned (type of return, destination, unaccompanied minors). Commission Implementing Decision (EU) 2021/431 granted some Member States derogations for 2021 to 2023. source · page
  • 2021, Eurostat: Eurostat flags a break in time series in migr_eirtn for 2021. source · page
  • 2021, Eurostat: Eurostat flags that the definition differs (see metadata) in migr_eirtn for 2021. source · page

50 more on the topic's pages.