How to find boat hin number?
On US-built boats, the primary Hull Identification Number is stamped on the starboard outboard side of the transom, within two inches of the top of the transom, gunwale or hull/deck joint, whichever is lowest. Boats without a usable transom carry it on the starboard aft hull near the stern. Once you have it, you can check your boat against the U.S. Coast Guard recall records by manufacturer, model, MIC or recall number.
Say you have just bought a second-hand skiff and the seller mentions a recall years ago. You want to check it properly. First you need the boat's Hull Identification Number, then you need to match it against official records. That is the workflow this article walks through, with a clear line between what the rules establish and what they leave to you.
[1][2]Where the HIN is marked
The US federal rule at 33 CFR 181.29 requires two identical hull identification numbers on the boat. On a boat with a transom, the primary HIN goes on the starboard outboard side of the transom, within two inches of the top of the transom, gunwale or hull/deck joint, whichever is lowest. On a boat without a usable transom, it goes on the starboard aft hull within one foot of the stern, again within two inches of the top of the hull side, gunwale or hull/deck joint. Replaceable-hull catamarans and pontoons have a separate aft-crossbeam location. The duplicate number sits in an unexposed interior location or beneath hardware, and both numbers must be permanently affixed.
[1]One caution: this is a United States rule. It is not a guarantee for every foreign-built, antique or undocumented boat, so if your boat does not match the pattern, ask the manufacturer or your boating authority rather than assuming.
[1]What you can check once you have identifying details
Even before you have the HIN in hand, you can make progress. The Coast Guard recall database can be searched by MIC (Manufacturer Identification Code), company name, recall number, model and model year. The recall list shows entries such as Carolina Skiff, Brunswick Family Boat Co and Bombardier Recreational Products, each with a recall number, the affected model names and the date the case was opened. So a boat's make and model, plus any paperwork naming the manufacturer, is often enough to find whether a recall case exists.
[2]A concrete comparison
Hypothetical: two owners, same task. The first has her registration document to hand, which names the builder and model. She searches the recall index by manufacturer and model, finds a matching case, and then contacts the builder with her HIN to confirm whether her hull falls inside the affected range. The second owner has no paperwork at all. He cannot search by manufacturer because he does not know who built the boat. His practical route is to find the HIN on the transom or interior duplicate first, then work outward from the builder it identifies. Same database, different starting points, and the first owner's route is plainly shorter.
[1][2]Checking the record properly
- Write down the manufacturer, model, model year and any recall or case number you find on paperwork or labels.
- Search the U.S. Coast Guard recall records by MIC, company, model or recall number rather than guessing.
- If a case matches, read the affected model or hull range in the official record and confirm with the manufacturer whether your specific boat is covered.
- Remember the limits: a search that returns no matching record is not a safety clearance and is not proof that no recall exists.
- Keep in mind that an equipment approval record and a recall record are separate datasets; one does not imply the other.
The recall search tool on this site works the same way: you search dated recall entries by manufacturer, model, MIC or case number, and a match points to an official case whose affected hull or serial numbers you then check with the manufacturer. Always open the underlying official record before acting.
[3]Your next step: check the starboard outboard transom for the primary HIN, or the interior duplicate if the outside marking is unreadable. Then gather the boat's make, model and any registration paperwork, run a search on the Coast Guard recall index by manufacturer or MIC, and if a case appears, contact the manufacturer with your HIN to confirm coverage.
[1][2]Sources and dates
- https://www.ecfr.gov/current/title-33/chapter-I/subchapter-S/part-181/subpart-C/section-181.29 · accessed 2026-10-18
- https://uscgboating.org/content/recalls.php · accessed 2026-10-18
- https://boatrecallcheck.com/ · accessed 2026-10-18