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How to Check a Boat Before Buying — A Due-Diligence Checklist

A used boat can hide an outstanding lien, a rebuilt-from-a-wreck history, a mismatched hull number, or a title that never transfers cleanly. None of that is visible on a sunny sea trial. This checklist is the order of operations for buying a boat with your eyes open — starting with the free checks that cost nothing but a few minutes, and ending at the paperwork that actually transfers ownership.

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TL;DR

Verify the HIN on the hull matches the paperwork; run a title and lien check; search USCG documentation status; commission an independent survey; do a sea trial under load; then close with a proper bill of sale and the correct state transfer. Do the free checks (HIN decode, USCG search) first — they can end a bad deal before you spend a dollar on a survey.

1. Verify the HIN — on the hull, not just the paper

Every boat built since November 1, 1972 has a 12-character Hull Identification Number permanently affixed to the starboard side of the transom, with a duplicate hidden elsewhere on the hull. Find it physically and confirm it matches the title, registration, and listing exactly.

A HIN that is missing, altered, ground down, or that doesn't match the paperwork is a stop sign — it can indicate a stolen hull or a rebuilt total loss. Decode the number with the free HIN decoder to confirm the manufacturer and model year line up with what the seller claims. A 2005-model boat whose HIN decodes to 1998 is a conversation you want to have before, not after, the sale.

2. Check the title and liens

Get the title in hand and confirm the seller's name matches it. A boat sold with a lien still attached can be repossessed from you even after you pay the seller — the lienholder's claim follows the boat.

For state-titled boats, the state title record shows the owner and any recorded lienholder. For a federally documented vessel, financing usually shows up as a Preferred Ship's Mortgage on the Coast Guard's abstract of title — order the abstract from the NVDC or confirm status through the free USCG vessel search. Never take "it's paid off" on faith; make the release of any lien a condition of closing.

3. Search USCG documentation status

If the boat is (or was) federally documented, confirm its current status directly. The Coast Guard's public records let you look up a documented vessel by name, official number, or HIN and see its documentation status, hailing port, and particulars.

Use the free USCG vessel search to confirm the documentation is current and the vessel details match. If the seller claims the boat is documented but you can't find it, or the record doesn't match the hull in front of you, slow down. Understanding whether the boat should be documented or state-registered at all is covered in registration vs documentation.

4. Consider a paid history report

The free checks above catch a lot, but they won't surface an out-of-state accident, an insurance total-loss, or a theft record from another jurisdiction. A paid boat-history report aggregates those records. It is optional and not always worth it — see the honest boat-history-report comparison, which starts by listing what you can check for free — but on an expensive or suspicious purchase it can be cheap insurance.

5. Get an independent survey

On any boat worth more than a few thousand dollars, hire your own accredited marine surveyor — not one the seller recommends. A survey covers hull moisture, structural integrity, engine condition, electrical and fuel systems, and safety gear, and it produces a written report that doubles as a negotiating tool and an insurance/financing requirement.

Pay for the survey yourself so the surveyor answers to you. A good survey routinely pays for itself in either avoided disasters or a corrected price.

6. Sea trial under real conditions

Run the boat the way you'll use it: reach cruising RPM, hold it there, and watch temperature, oil pressure, and how it tracks and handles. Check that it planes (if it should), that the transmission engages cleanly in both directions, and that electronics, bilge pumps, and steering work under way. A cold-start-in-the-driveway demo is not a sea trial. Ideally the surveyor attends.

7. Close with a proper bill of sale and state transfer

The bill of sale should list the full HIN, year/make/model, the agreed price, the date, and both parties' names and signatures. It is your proof of the transaction and the price (which matters for sales tax).

Then complete the transfer with the right authority: for a state-titled boat, submit the signed title and bill of sale to the state (in Florida, the county tax collector — see the Florida registration guide); for a documented vessel, file a transfer of ownership with the NVDC. Get liens released in writing at or before closing, and don't hand over money until the paperwork is in order.

Planning to charter or take paying passengers?

If your plan for the boat is to carry passengers for hire — charter fishing, tours, or sunset cruises — buying the boat is only half of it: the operation itself requires a USCG captain's credential. A boat carrying up to six paying passengers needs an operator with at least an OUPV "six-pack" license. If you're not sure whether your intended use crosses into passenger-for-hire, start with do I need a captain's license.

Frequently asked questions

What should I check before buying a used boat?

In order: verify the HIN on the hull matches the paperwork, check the title and any liens, confirm USCG documentation status if applicable, optionally pull a paid history report, commission your own marine survey, run a real sea trial, and close with a full bill of sale and the correct state or federal transfer. Do the free HIN and USCG checks first.

How do I check a boat's HIN?

Find the 12-character Hull Identification Number physically on the starboard side of the transom and confirm it matches the title, registration, and listing. Then decode it to confirm the manufacturer and model year are consistent with the seller's claims. A missing, altered, or mismatched HIN is a serious warning sign.

Can a used boat have a lien I don't know about?

Yes, and the lien follows the boat — a lienholder can repossess it from you even after you have paid the seller. Check the state title record for a recorded lienholder, or for a documented vessel review the Coast Guard abstract of title for a Preferred Ship's Mortgage, and make any lien's release a written condition of closing.

Is a marine survey worth it on a used boat?

On any boat worth more than a few thousand dollars, almost always. An independent surveyor you hire (not one the seller picks) inspects the hull, engine, and systems and produces a report you can use to negotiate — and that lenders and insurers often require. It routinely pays for itself.

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Boat Buying Checklist — How to Check a Used Boat (2026) · CaptainsGround