To get a VIN for a trailer, you apply through your state DMV, bring documentation of the trailer and its parts, submit the trailer for a physical inspection, and pay a fee. The agency then issues a VIN plate or decal that gets permanently attached to the frame, and you use that paperwork to title and register the trailer. Details vary by state, but the sequence is the same almost everywhere.
When You Need a State-Assigned VIN
Factory-built trailers already carry a 17-character VIN assigned by the manufacturer under federal rules.1NHTSA. Importation and Certification FAQs If your trailer came from a dealer with a clean title, the number is already there. You don’t need a new one.
You do need a state-assigned VIN in three common situations:
- You built the trailer yourself.
- You acquired a trailer whose original VIN plate is missing, destroyed, or unreadable.
- You have a salvage or rebuilt trailer whose prior identification no longer applies.
Some states also assign a new VIN when a trailer is imported or built from a kit.
Before you start, check the weight threshold in your state. Many states exempt very light trailers from titling entirely. Thresholds vary widely, but trailers under roughly 1,000 to 3,000 pounds unladen weight may not need a formal VIN or title at all. A phone call to your local DMV can save you the whole trip.
Documents and Information to Gather
Showing up without the right paperwork is the fastest way to lose a day. States use their own forms, but the underlying information is consistent. Have this ready before you contact the DMV:
- Original receipts for the axles, frame, wheels, lights, and other components. These show you legitimately acquired the parts.
- A bill of sale if you bought the trailer or a partial build from someone, signed and dated, with the price and a description of what changed hands.
- A weight slip from a certified public scale. Unladen weight determines which application path you follow and whether a title is even required.
- The trailer’s specifications: overall length and width, number of axles, gross vehicle weight rating if known, and type (utility, boat, enclosed cargo, flatbed).
- Proof of insurance for the vehicle that will tow the trailer to the inspection site. Some states check for this.
- The state’s VIN application form, filled out in advance.
For a rebuilt or salvage trailer, bring any prior title, salvage certificate, or junk certificate you have, along with documentation of the repairs.
The Inspection
Almost every state requires someone to physically look at the trailer before issuing a VIN. In some states a DMV field investigator handles this. In others it’s a law enforcement officer. Either way, the inspector verifies that the trailer exists, matches your paperwork, and meets basic safety requirements.
Expect them to check that the trailer’s physical characteristics line up with your application, that parts receipts correspond to what’s actually installed, and that required lights and safety equipment work. Heavier trailers get a more thorough look. Some states set a specific weight above which law enforcement, not DMV staff, must do the inspection.
You’ll usually need to schedule the inspection rather than walk in. The agency tells you where and when to bring the trailer. Since your trailer can’t be registered without a VIN, ask about a temporary transport permit that lets you legally tow it to the inspection site. Several states issue these as part of the application.
Fees
VIN assignment fees are generally modest and come in two parts: a fee for the examination or inspection, and a smaller fee for the VIN plate or decal. The inspection fee ranges from under $10 to more than $100 depending on the state. The plate itself is usually only a few dollars.
Those fees cover assignment only. Titling and registration come with their own fees, based on your state’s schedule and the trailer’s weight class. Budget for both rounds.
Attaching the VIN
Once the VIN is assigned, it must be permanently affixed to the trailer. Federal regulations require the VIN to appear “clearly and indelibly” on a part of the vehicle not designed to be removed except for repair.2eCFR. 49 CFR 565.13 – General Requirements In practice that means a metal plate riveted to the frame or tongue, or a decal applied to a structural component.
In most states the inspector or DMV staff attaches the plate during the inspection appointment. You don’t do it yourself. The official has to witness the attachment to certify it was done correctly. Afterward you’ll receive signed paperwork confirming the VIN assignment, which you’ll need for titling.
Titling and Registering the Trailer
The VIN assignment alone doesn’t make the trailer road-legal. Take your VIN paperwork, proof of insurance if your state requires liability coverage for trailers, and payment for title and registration fees back to the DMV. The agency issues a title in your name and provides plates or a registration sticker.
Keep every document from this process. The VIN application, inspection certificate, title, and registration together form a complete ownership chain. If you ever sell the trailer, the buyer will want to see that chain, and a gap can kill the sale or raise questions about where the trailer came from.
What to Do When You Have No Proof of Ownership
If you have a trailer but no paperwork showing you own it, most states won’t simply hand you a VIN and a title. You may have inherited a trailer from a relative who never titled it, bought one at a yard sale without a bill of sale, or found one abandoned on your property.
Many states solve this with a bonded title. You buy a surety bond worth one to one-and-a-half times the trailer’s appraised value, and the state issues a title with a “bonded” notation. The bond protects anyone who later comes forward and proves they’re the rightful owner. If nobody does within the state’s waiting period, typically three to five years, the title becomes clean and unrestricted.
The premium is a fraction of the bond’s face value. For most trailers, expect somewhere in the $100 to $250 range depending on the trailer’s value and state requirements. Not every state offers bonded titles, and some use alternatives like court-ordered titles. Confirm with your DMV before buying a bond.
Don’t Tamper With an Existing VIN
If your trailer already has a VIN, leave it alone. Under 18 U.S.C. ยง 511, knowingly removing, altering, or covering a VIN carries up to five years in prison and a fine.3Office of the Law Revision Counsel. 18 USC 511 – Altering or Removing Motor Vehicle Identification Numbers Possessing a trailer with a VIN you know was tampered with is also a crime and carries up to one year in prison, even without proof you did the tampering.
Narrow exceptions exist. You can remove or alter a VIN during a repair if doing so is reasonably necessary, and you can restore or replace a VIN under your state’s law. None of those exceptions apply if you know the trailer is stolen.3Office of the Law Revision Counsel. 18 USC 511 – Altering or Removing Motor Vehicle Identification Numbers
If a trailer you’re considering has a suspicious VIN, walk away. If you want to buy it anyway, ask your local law enforcement to run a VIN check before any money changes hands. A cheap trailer that draws you into a federal investigation is not a cheap trailer.