How many unique individuals (de‑duplicated) have been estimated to cross the U.S. border illegally since 2020?

1. How the government counts crossings — encounters, not unique people

U.S. Customs and Border Protection publishes “encounters,” a composite measure that includes Border Patrol apprehensions, Office of Field Operations inadmissibles at ports of entry, and expulsions under Title 42, and that metric deliberately counts each encounter event rather than every unique person ^{[4] [5]}.

2. The raw scale since 2020: roughly 10.8 million encounters since FY2021

A House Homeland Security Committee fact sheet summarized CBP reporting as about 10.8 million total encounters since fiscal year 2021 and separately highlighted roughly 2 million recorded “gotaways” in the same period, producing the frequently cited multi‑million encounter totals ^[1].

3. Why encounters overstate unique individuals: recidivism and Title 42 effects

CBP and outside analysts explicitly warn that encounters can include the same person multiple times; during the Title 42 period (March 2020–May 2023) expulsions and rapid returns produced higher repeat‑attempt rates, meaning “the actual number of unique individuals attempting to cross the border was substantially lower than total encounters,” according to CBP commentary reproduced in USAFacts reporting ^{[2] [4]}.

4. What de‑duplication efforts show — partial, technical, and limited

The Office of Homeland Security Statistics (OHSS) and CBP maintain data systems that can de‑duplicate some records and report low overlap rates across certain datasets (for example, OFO de‑duplication rates under 0.1 percent for inadmissibles), but those technical de‑duplications do not translate into a clean public total of unique cross‑border entrants covering all encounter types and the period since 2020 ^[3].

5. Published breakdowns that inform but don’t resolve the question

Public fact‑checks and reporting offer useful aggregates — for example, fact‑checking summaries cite CBP figures showing millions of encounters with roughly 2.5 million people released into the U.S. and about 2.8 million removed or expelled in initial processing — but those release/removal counts still do not equate to de‑duplicated unique entrants across the 2020–present window ^[6]. The Homeland Committee’s tally of 5.50M single adults, 2.66M family‑unit individuals, and 546,255 unaccompanied children since FY2021 gives a demographic slice but again reflects encounter events rather than a deduplicated headcount ^[1].

6. A reasoned estimate and its limits: “several million” unique individuals

Bringing these sources together, the public record supports a cautious, evidence‑based conclusion: total encounters since 2020/ FY2021 approach 10–11 million, but because CBP and OHSS both say repeat attempts are common (especially under Title 42) and because official public data do not publish a single de‑duplicated tally, the number of unique individuals who crossed or attempted to cross illegally since 2020 is not publicly available as a precise figure; based on encounter totals and documented recidivism, the universe of unique individuals is best described as being in the low‑to‑mid millions rather than the single‑ or double‑digit millions often claimed in political rhetoric ^{[1] [2] [3] [6]}.

7. Where claims diverge and how to read competing numbers

Political claims that “8–10 million have come in illegally” or that most encounters equal unique releases conflate encounter events with distinct people; fact‑checkers and CBP data both show that encounters, expulsions, releases, and removals are overlapping categories and that published encounter sums therefore cannot be taken at face value as de‑duplicated migration counts ^{[6] [5]}. Some congressional summaries emphasize the largest possible sums (encounters + gotaways) to make a political point; the data-producing agencies caution readers about recidivism and dataset limits ^{[1] [2]}.

8. Bottom line and what’s missing from public data

The publicly available documents permit an evidence‑informed range — total encounters since 2020 are on the order of 10–11 million (FY2021 onward) but the de‑duplicated number of unique individuals is not published and therefore cannot be stated precisely from available sources; the most supportable characterization is “several million unique individuals,” with the caveat that improved, public de‑duplication by DHS/CBP would be required to move from an estimate to a definitive count ^{[1] [2] [3]}.