These flows have been very difficult to track.  I have not attempted my own estimate. Here is a Brookings Institution paper issued in January 2026. The graphic of recent flows is easy to read. Since this report, some estimates have been made of total and net migration, but due to recent TPS terminations and continued ICE enforcement escalation any estimate of new migration numbers as of now (Sept 2026) are tentative.

Some persons legally in the U.S. are accounted for as “undocumented.” This is literally not true: hundreds of thousands are in TPS or Humanitarian Parole, known and traceable, but sometimes listed as undocumented.

One of the unknowable facts is how may person who were unauthorized or about to be unauthorized (such as TPS beneficiaries) have left the United States without any official notification. There has always been a regular churn every year. Brookings estimates that about 200,000 left in 2025 above an expected normal churn, and that this number may be a half million in 2026.