Expanding the Net: What the New 24-Mile CBP Maritime Zone Means for Cruisers

If you run the stretch between Puerto Rico, the Spanish Virgins, and the USVI, here’s something that changed under you without much fanfare.

On August 25, 2026, U.S. Customs and Border Protection quietly doubled its marine enforcement reach — from 12 nautical miles to 24 — in four zones around the country, one of them wrapped around Puerto Rico. That zone explicitly includes Mona, Desecheo, Vieques, and Culebra. So if you’re island-hopping through the Spanish Virgins, you’re now sailing through it.

The target is smuggling, not cruisers. But the water you’re in just got a lot more federal.

Why 12 Miles Wasn’t Enough

For decades, 12 nautical miles marked the edge of U.S. territorial waters — the line international law drew. Smugglers knew that line as well as anyone, and plenty of them worked it: stage a boat just past 12 miles, transfer the load, run it ashore before anyone official showed up.

CBP just closed that gap, at least here. The new zone reaches all the way to 24 miles — the outer edge of what’s called the contiguous zone, a distance the U.S. has technically claimed since a 1999 presidential proclamation but never fully enforced — using authority from the Anti-Smuggling Act of 1935. Inside that 12-to-24-mile band, CBP Air and Marine Operations and the Coast Guard can now stop, board, and inspect a vessel they suspect of breaking customs, immigration, or fiscal law. Not “might eventually.” Can, today.

One Thing Worth Getting Straight: This Is Puerto Rico’s Zone, Not a USVI Zone

Here’s the nuance CBP’s own paperwork doesn’t spell out for you: the zone is drawn around Puerto Rico and its outer islands — Mona, Desecheo, Vieques, Culebra. The USVI isn’t named anywhere in the federal notice. But look at a chart — Culebra and Vieques sit close enough to St. Thomas and St. John that the 24-mile ring drawn around them reaches right into the water you’d cross getting from one to the other anyway. So the distinction is real on paper and irrelevant on the water. If you’re running that passage, you’re in the zone. Full stop.

And No, It’s Not Nationwide — Yet

Worth being precise here: this isn’t a blanket U.S. policy. CBP stood up exactly four of these zones on the same day — South Florida, the Texas Gulf Coast, Central/Southern California, and Puerto Rico. The U.S. Virgin Islands isn’t one of them. Neither is American Samoa, Guam, Hawaii, or anywhere else. This is CBP moving first in four of its highest-traffic smuggling corridors, not a coast-to-coast rule.

That said, don’t assume it stops there. There’s a bill in Congress right now — the Extending Limits of U.S. Customs Waters Act — that would write the full 12-to-24-mile expansion into law nationwide. The zone already legally exists everywhere under that 1999 proclamation; CBP just hasn’t had the operational mandate to work it everywhere. Four regions just got that mandate. More may follow.

What Changes for You

Nobody’s coming for the average cruiser here — this is aimed at trafficking. But you’ll feel it:

• You’ll see more of them. More interceptors, more armed marine units, more aircraft overhead, farther offshore than you’re used to.
• The whole corridor counts now. Culebra to Vieques to St. Thomas to the mainland — that entire stretch sits inside active federal enforcement water.
• Check in, every time. Moving between the BVI, USVI, and Puerto Rico means using CBP ROAM and following port-of-entry rules to the letter. This isn’t the year to get lazy about it.

This Isn’t a Warning Shot — It’s Already Happening

CBP has been building to this since March 2026, when they first told small-vessel operators: report in before moving between Puerto Rico and the USVI, and do it through the ROAM app. Skip it, and the fine starts at $5,000. Three vessels have already been stopped and their captains fined. That’s before the zone even doubled. Expect that number to climb, not level off.

Know where the line is, check in every time through ROAM, and your island-hopping stays exactly as easy as it’s always been. Skip that step, and it won’t.

captain has written for ALL AT SEA since 2020.