What you need to register a trailer in California
Trailer registration in California happens through the Department of Motor Vehicles (DMV), and the process depends on what kind of trailer you own and whether it's new or used. You'll need to visit a DMV office or use their online services, bring proof of ownership, pay a registration fee, and get a certificate of registration and license plate. The fee varies based on the trailer's weight and type — a utility trailer costs less than a commercial or RV trailer.
California requires all trailers to be registered before you tow them on public roads, even if you're only moving it once. The registration is tied to the trailer itself, not to you as the owner, so it stays with the vehicle if you sell it (though you'll need to transfer ownership separately).
Key Takeaways
- You must register your trailer at a DMV office or online before towing it on California roads, and registration fees depend on the trailer's weight and type.
- Bring your proof of ownership (title, bill of sale, or manufacturer's statement), a completed process for Title or Registration (Form REG 343), and payment to the DMV.
- New trailers need a manufacturer's statement of origin; used trailers need a title or bill of sale from the previous owner.
- Registration takes about two weeks by mail or can be completed the same day at a DMV office, and your license plate arrives separately in the mail.
Documents you need to bring to the DMV
Start by gathering your proof of ownership. If you bought a new trailer from a dealer, you'll have a manufacturer's statement of origin (MSO). If you bought a used trailer, you need either the title from the previous owner or a bill of sale signed by both of you. If the trailer has no title (common for older or homemade trailers), you may be able to get a statement from the seller under penalty of perjury, though this varies by DMV office.
Next, fill out Form REG 343 (process for Title or Registration). You can read this from the DMV website or pick one up at any DMV office. You'll also need a form of identification — a driver's license, passport, or state ID. Bring your vehicle identification number (VIN) if the trailer has one; many utility trailers don't, and that's fine.
Finally, bring payment. Fees depend on the trailer's dry weight (the weight without cargo). A utility trailer under 1,500 pounds costs less than a commercial trailer or travel trailer. The DMV website has a fee calculator where you enter the weight and type to see the exact amount.
How to register online versus in person
The DMV allows some trailer registrations online through their website, but only if you meet certain conditions: the trailer must have a current registration you're renewing, or you must be transferring registration from another vehicle you own. If you're registering a trailer for the first time, you'll need to visit a DMV office in person or mail in your documents.
Registering in person at a DMV office usually takes 30 minutes to an hour, and you walk out with your certificate of registration the same day. Your license plate arrives by mail within two weeks. If you mail in your documents, the whole process takes about three weeks. You can find your nearest DMV office and check wait times on the DMV website before you go.
Registration fees and what they cover
California registration fees for trailers are based on the dry weight of the trailer, not its value. A utility trailer under 1,500 pounds might cost $50 to $80 to register, while a heavier commercial or RV trailer could cost $150 to $300 or more. The DMV website has a complete fee schedule broken down by weight category and trailer type.
Your registration fee covers the certificate of registration (a paper document) and one license plate. The plate is metal and must be mounted on the back of the trailer. If you lose the plate or need a replacement, there's an additional fee. Registration is valid for two years in California, and you'll need to renew it before it expires.
Renewing your trailer registration
Before your registration expires, the DMV mails you a renewal notice. You can renew online, by mail, or in person at a DMV office. Online renewal is the fastest — you log into your DMV account, pay the fee, and your new registration is processed within days. By mail, send the renewal notice with your payment to the address listed on the form. In person, bring the notice and payment to any DMV office.
If you miss the expiration date, you can still renew, but you may owe a late fee on top of the regular registration cost. If your trailer's weight has changed significantly (for example, you added a cargo box), you may need to update that information when you renew, which could change your fee.
Special situations: homemade trailers and out-of-state transfers
If you built your own trailer or bought one without a title or VIN, California allows you to register it, but the process is different. You'll need to get a statement from the seller (or your own statement if you built it) under penalty of perjury, and the DMV may require an inspection to verify the trailer's condition and safety. Contact your local DMV office before you go to ask what documents they need for a homemade trailer.
If you're moving to California with a trailer registered in another state, you have 20 days to register it in California. Bring your out-of-state title or registration, proof of California residency (like a lease or utility bill), and your identification. The DMV will issue you a California title and registration. Your out-of-state plate is no longer valid once you register in California.
What happens if you tow without registration
Towing an unregistered trailer on California roads is a violation, and you can be cited by law enforcement. The fine depends on the circumstances, but it's typically $100 to $250 for a first offense. More importantly, if you're in an accident while towing an unregistered trailer, your insurance may not cover the damage, and you could be held liable for the full cost.
If you've been towing an unregistered trailer, register it as soon as you can. The DMV doesn't penalize you for late registration — you straightforward pay the current fee and get your certificate. If you've received a citation, you may be able to show proof of registration to the court to reduce or dismiss the fine, depending on when you registered relative to the citation date.
Frequently Asked Questions
Do I need to register a trailer if I only use it on private property?
No. California only requires registration for trailers towed on public roads. If you keep your trailer on your own land and never tow it on streets or highways, you don't need to register it. Once you tow it on any public road, even to cross a street, registration is required.
Can I register a trailer without a VIN?
Yes. Many utility trailers, especially older ones, don't have a VIN. The DMV will register the trailer without one. You'll provide other identifying information like the make, model, year (if known), and color. If the trailer has a VIN, you must provide it.
What if the previous owner didn't sign the title or bill of sale?
Contact the previous owner and ask them to sign the document. If you can't reach them, you can ask the DMV about filing a statement under penalty of perjury explaining the situation. Some DMV offices will accept this; others may require an inspection. Call your local office first to ask what they need.
How long does registration take if I do it by mail?
Mailing in your documents typically takes two to three weeks from the time the DMV receives them. Your certificate of registration arrives by mail, and your license plate arrives separately, usually within a few days of the certificate. You can start towing once you receive the certificate, even if the plate hasn't arrived yet.
Do I need to register a trailer I'm borrowing from someone else?
No. The trailer is registered to its owner, not to whoever is towing it. As long as the trailer has a current registration and valid license plate, you can tow it legally. Make sure you have the owner's permission and that their insurance covers you as a driver.