Most trailers in California are registered under the DMV's Permanent Trailer Identification (PTI) program: a PTI card, a plate, and a service fee every five years instead of annual renewal. Park trailers and trailer coaches are the exceptions. If the trailer has no title, the paperwork depends on whether a paper title was ever issued: the DMV says a bill of sale can transfer a PTI trailer only when no paper title exists. The DMV's trailer registration instructions list the forms. Via Rapida Services is a licensed registration service and insurance agency, not the DMV.
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The DMV's commercial vehicle registration page says all trailers are registered under PTI except park trailers and trailer coaches, which are registered annually. Which one you have decides the rest of the paperwork.
| Trailer | How the DMV treats it |
|---|---|
| Utility trailer (personal property, not more than 10,000 lb gross or GVWR) | PTI |
| Other trailers that carry persons or property on their own structure, including semi-trailers | PTI |
| Camp trailer (tent trailer or similar, up to 16 ft overall and 96 in wide) | PTI |
| Travel trailer or fifth-wheel that is larger than a camp trailer | Trailer coach: annual registration, not PTI |
| Park trailer (400 sq ft or less, recreational use, moved by Caltrans permit) | Excluded from PTI: annual registration |
| Coach boat trailer (a trailer coach with a hull) | Excluded from PTI: annual registration |
| Tow dolly or auxiliary dolly | Not required to be registered in California, but you may choose PTI. The DMV suggests it if you will tow out of state |
These categories come from the DMV's PTI definitions and excluded trailers sections. A manufactured home is not a DMV matter at all: the DMV says units built to HUD standards are licensed and titled by the Department of Housing and Community Development.
| What you have | What the DMV asks for |
|---|---|
| A signed California paper title | The same steps as any private transfer: the title signed by the seller and the buyer, and the transfer fee. The DMV's PTI transfer section says the requirements are the same as for other vehicles, with the extra forms below. See our title transfer guide. |
| A bill of sale and no paper title, because the DMV never issued one to the trailer's PTI owner | A PTI Certification (REG 4017) with Side B completed. The form says that if a certificate of title was not requested, a bill of sale can be used for transfer of ownership. The seller completes Sections 1 and 2 and the buyer completes Sections 4 through 7 as needed. A duplicate title fee is not due because no title was issued. |
| A paper title was issued but is lost | The Application for Replacement or Transfer of Title (REG 227) and the duplicate title fee. A bill of sale does not replace a paper title that exists: the REG 4017 says that once a physical title has been issued, it must be used on transfer. |
| A new trailer bought in another state | The titling document (an out-of-state title, a manufacturer's statement of origin, or a REG 397 from a dealer). If there is no REG 397, the DMV also asks for a REG 343, a REG 31 and a REG 256, described below. |
| A used trailer from another state, or one that DMV has no record of | The out-of-state title if there is one, the REG 343, a verification of vehicle (REG 31) and a REG 256 stating the unladen weight. Our out-of-state registration guide covers the title side. |
| A homemade or kit-built trailer | The DMV's verification rules say a specially constructed motor vehicle or trailer always needs a verification of vehicle. Ask the DMV before you buy or build, because the paperwork is different from a factory trailer. |
Two cautions. First, a bill of sale is a document of the sale; it is the DMV record that decides whether a title exists. Ask the seller for the PTI card and the plate number so you can check. Second, the DMV's unavailable-records procedure says that trailer coaches must be currently registered at all times, so a lapsed coach cannot be treated like a PTI trailer.
The DMV's vehicle verification rules list when a physical inspection is required: a vehicle last registered out of state, a specially constructed trailer, and any vehicle the DMV has no record of. It is not required for a new trailer bought in another state that qualifies for PTI if the trailer was never registered, has not been modified, altered or assembled from a kit, and comes with a secure manufacturer's certificate or statement of origin for the complete trailer.
The authorized verifiers the DMV lists are DMV employees, peace officers, employees of auto clubs that provide registration services, and persons licensed by the DMV as vehicle verifiers. The verifier completes the REG 31, and the DMV says all the descriptive information on it must be physically inspected. For a trailer, the form also records axles and estimated weight. Our VIN verification guide explains the process.
Sometimes. The DMV's REG 4017 says that if a certificate of title was not requested for a PTI trailer, a bill of sale can be used for transfer of ownership, with Side B completed. If a paper title was ever issued, that title must be used instead.
Not always. The DMV says PTI trailers are not automatically issued a paper title unless there is a lienholder or legal owner. The owner can request one on REG 4017 Side A and pay a PTI title fee. Without a request, the DMV issues a PTI card and keeps an electronic ownership record.
The REG 4017 says the new owner must complete the transfer within 10 days of taking possession, and the DMV's title transfer page says ownership changes must be reported within 10 days.
Often, yes. The DMV requires a verification of vehicle (REG 31) for a trailer last registered out of state, a specially constructed trailer, and a trailer the DMV has no record of. A new trailer from another state with a secure manufacturer's statement of origin that was never registered or modified is the exception. See the DMV's verification rules.
Not a PTI trailer. The DMV says PTI trailers pay a service fee every five years, or file a Planned Non-Operation certification, and no new sticker is issued. Park trailers and trailer coaches are registered annually.
The DMV says a tow or auxiliary dolly is not required to be registered in California, but you may register it as PTI. It suggests doing so if you will tow it out of state because other states' rules vary.
Reviewed by Santo Militello, California-licensed Property & Casualty agent (CA License #1737723) and owner of Via Rapida Services. Insurance City Agency, LLC · CA License #6003045. Our licensed team brings more than 70 years of combined insurance experience. Call (209) 670-1556. Last reviewed 2026-10-09.
La guía para registrar un remolque o traila en California está escrita en español.
Talk with a licensed agent about how a trailer fits your policy. The DMV decides what it requires for the title and registration.