Despite Uptick in September, FY25 Border Arrests Were the Lowest in Generations

The congressional budget shutdown delayed CBP’s release of its nationwide “encounters” figures for September, but they finally appeared on Friday. The bad news is that Border Patrol apprehensions of illegal migrants at the Southwest border ticked up in September. The good news is that FY 2025 ended with the lowest yearly total for apprehensions in the past 55 years – and likely the lowest total number of illegal entries since the 1940s. 

Border Patrol Apprehensions

Nationwide in September, Border Patrol agents apprehended just over 10,200 illegal migrants, the majority (82.2 percent or 8,386) of those apprehensions occurring at the Southwest border. 

That’s a 26-percent month-over-month rise nationwide compared to August (8,085 apprehensions) and a 32.8 percent increase at the U.S.-Mexico line. 

That’s a problem because, aside from during the Biden administration (when migrant trends were unpredictable), apprehensions historically decline between August and September.

Don’t get too concerned yet, however, because apprehensions are coming off a historic nadir set in the first few months of the Trump II administration. The 4,592 Southwest border apprehensions in July were the lowest monthly total in recorded history (records go back to October 1999). 

Last month’s Southwest border apprehension total was just 15.6 percent what it had been in September 2024 (nearly 54,000), and for that matter was just one-fifth the total in September 2019 (40,507), when the Trump I migrant-return policy, “Remain in Mexico”, was in high gear.

Still, fewer illegal entries are preferable to more, so the president, CBP Commissioner Rodney Scott, and “border czar” Tom Homan are likely scheming to push the trendline lower. 

Total FY 2025 Apprehensions

September is the last month of the federal government’s fiscal year, which means last month’s apprehension total completes the annual total. And that FY 2025 annual total likely makes Trump, Scott, and Homan very happy. 

That’s because all told, nationwide, across all our nation’s borders (Southwest, Northern, and Coastal) agents apprehended 237,538 illegal entrants, 15.5 percent as many as in FY 2024 (1.530 million-plus) and 88.4 percent fewer than in FY 2023 (nearly 2.046 million). 

More importantly, that’s the lowest nationwide apprehension total for Border Patrol since FY 1970, when agents nabbed 231,116 illegal migrants nationwide. 

In the absence of a better metric, “experts” use Border Patrol apprehensions as substitute for the total number of illegal entrants. When apprehensions go up, they assume, illegal entries are rising as well. 

The problem with using apprehensions to quantify total illicit entries decades ago is that agents in the distant past apprehended a much lower percentage of illegal migrants than they do today. 

That’s not a knock on the agents – Border Patrol was wildly understaffed prior to September 11th, and the infrastructure improvements agents rely on today (fencing, border-adjacent roads, ground sensors, cameras, lights, etc.) weren’t in place back then. 

As recently as FY 2000, the Border Patrol “apprehension rate” at the Southwest border was just 42.5 percent, according to DHS estimates, which means that for every 43 illegal migrants agents apprehended, more than 57 others entered without being caught.

As recently as FY 2000, the Border Patrol “apprehension rate” at the Southwest border was just 42.5 percent. Today the apprehension rate is closer to 92 to 95 percent. 

Today the apprehension rate is closer to 92 to 95 percent, and as more infrastructure is installed using the $46 billion in funding H.R. 1, the “One Big Beautiful Bill Act”, allocated for such purposes, that rate will likely climb further. 

Anecdotally, the apprehension rate prior to the 1990s was closer to a quarter to a third of all illegal Southwest border migrants – and I was around to hear such anecdotes, given my immigration career began under the George H.W. Bush administration in 1992. 

The Border Patrol apprehension rate was so low, in fact, that less than half of would-be migrants in the 1970s bothered hiring smugglers; they just crossed. More recently, an estimated 80 to 95 percent of illegal crossers came here with smugglers. 

In any event, that suggests that if fewer than 232,000 illegal Southwest border migrants were caught in FY 1970, somewhere between 670,000 and 800,000 aliens (mostly single adult males from Mexico seeking seasonal employment) in total made the trip. 

Conversely, using a conservative (low-end) 92 percent apprehension rate for FY 2025, those 231,116 migrant entries represent around 251,250 total attempted entries.

Using that similarly conservative (high-end) 33-percent apprehension rate in earlier years, you must go back to FY 1945 – when there were 69,164 Border Patrol apprehensions representing nearly 207,500 total entries – to find a year in which fewer migrants attempted to cross the Southwest border illegally.

Things can change, and Trump’s border policies are being challenged, but if the border remains this secure through next September, CBP could be publishing FY 2026 apprehension figures in the five-digit range –a far cry from the more than 2.2 million encounters agents notched under Biden in FY 2022.