How many unique individuals (not encounters) crossed the southern border 2020–2024 according to DHS and academic estimates?
Executive summary
DHS/CBP public data count “encounters,” not unique people, and publicly released encounter totals for the southern border between roughly 2020–2024 run into the millions — roughly 10.8 million encounters since FY2021 as reported by congressional staff citing DHS/CBP data [1] and CBP/independent compilations that show about 11 million nationwide encounters through mid‑2024 [2]. DHS does not publish a definitive tally of unique individuals for 2020–2024 in the sources provided; applying a conservative repeat‑crossing adjustment (an 11% recidivism snapshot cited by CBP/DHS reporting) produces a midrange estimate of roughly 9.6 million unique individuals for the FY2021–FY2024 encounters window, but that figure is an approximation and not an official DHS “unique persons” count [3] [1].
1. What DHS actually reports: encounters, not unique people
DHS/CBP’s public metrics track encounters — defined to include Border Patrol Title‑8 apprehensions, Office of Field Operations Title‑8 inadmissibles, and Title 42 expulsions — and these encounter counts are repeatedly used in official fact sheets and KHSM reporting [4] [5] [6]. Congressional summaries and CBP monthly updates cite cumulative encounter totals — for example a “10.8 million total encounters since FY2021” figure highlighted by the House Homeland Security Committee and CBP reporting on southwest border trends — but those are encounter events, not deduplicated persons [1] [2].
2. How researchers and reporters try to convert encounters into people
Journalists and fact‑checkers note that encounter totals overcount individuals because some people are encountered multiple times, and they point to available internal metrics (like recidivism rates) to estimate unique persons; FactCheck pointed out that DHS data showed an 11% recidivism figure for August as an example, and used DHS breakdowns (removals/expulsions vs. releases) to illustrate how encounter totals can be misread [3]. DHS itself has published operational snapshots showing large numbers of removals/expulsions (2.8 million by one cited summary) and releases/other outcomes (about 2.5 million in one discussion), which underscores why encounters alone don’t map one‑to‑one to unique entrants [3].
3. A simple DHS‑based approximation and its limits
Using the encounter baseline cited by congressional and CBP materials — ~10.8 million encounters since FY2021 (a proxy for the 2020–2024 period in the available reporting) — and applying the 11% repeat‑crossing rate noted in DHS/CBP commentary yields an illustrative estimate of unique individuals of about 9.6 million (10.8M × (1 − 0.11)) [1] [3]. That arithmetic is straightforward but must be treated as an approximation: the 11% recidivism figure was a monthly snapshot, recidivism varied over time (including higher repeat attempts during Title 42-era incentives), and the encounter window in some reports covers Oct 2019–mid‑2024 rather than calendar 2020–2024, so the base encounter figure and repeat rate could shift the result materially [2] [3].
4. Why academics’ numbers aren’t in the provided reporting
The sources supplied here are DHS/CBP releases, House committee summaries, and journalism/fact‑check pieces; none of them include a peer‑reviewed academic estimate of unique individuals across 2020–2024, so an authoritative academic range cannot be produced from the materials provided [1] [2] [3]. Independent scholars sometimes publish deduplicated estimates using survey, administrative‑linkage, and statistical matching methods, but those methods and outputs are not present in the supplied documents, and therefore cannot be cited or reported here.
5. Bottom line and recommended caveats for readers
The official public record provides encounter totals (millions) but no DHS definitive count of unique individuals for 2020–2024 in the supplied sources [1] [5]; a DHS‑data based illustrative calculation using a cited 11% recidivism rate produces an approximate 9.6 million unique individuals for the ~10.8 million encounter universe, but this is an estimate, not an official figure, and could change if a different recidivism rate, different temporal window, or academic deduplication method is used [3] [2]. Readers should treat encounter counts and “unique person” estimates separately and demand transparent deduplication methodology before treating any single number as definitive [5].