California — quick answer
In California, a bill of sale is not required for a private vehicle sale and notarization is not required. No witnesses are required. The relevant state form is REG 135. Ownership is transferred through the California DMV via the assigned title.
Is a bill of sale required in California?
Not required. A bill of sale is optional. The DMV's REG 135 can stand in for the owner's release-of-ownership signature on the title.
Seller signs the title over to the buyer; the buyer submits the title (or REG 135) and applies for transfer within 10 days.
Does a California bill of sale need to be notarized?
Not required. California's registration manual states a bill of sale is not required to be notarized or witnessed.
Witness requirements
No. California does not require witnesses for a standard private bill of sale.
Odometer disclosure
Federal law requires a written odometer disclosure when title is transferred for vehicles less than 20 years old. As of 2026 that means model year 2011 and newer; model year 2010 and older are generally exempt. Record the exact mileage — never round it. See the NHTSA rule.
How to transfer a vehicle title in California
- 1Complete the bill of sale and title assignment.
Fill in the buyer, seller, price, odometer, and date. Both parties sign and date the document.
- 2Hand over the signed title.
Seller signs the title over to the buyer; the buyer submits the title (or REG 135) and applies for transfer within 10 days.
- 3File a notice of sale / release of liability.
As the seller, file Notice of Transfer and Release of Liability (file within 5 days) so you are not liable for the vehicle after the sale.
- 4Register with the California DMV.
The buyer titles and registers the vehicle, bringing Bill of Sale (REG 135). Confirm the current fees and documents on the official California DMV page.
Official California sources
- California Department of Motor Vehicles (DMV) — buying & selling a vehicle
- Bill of Sale (REG 135)
- NHTSA — federal odometer disclosure rule
We link to primary government sources and review this page regularly, but requirements change. This is general information, not legal advice.
California bill of sale by type
Get requirements and a free template tailored to California for each item type — the generator applies the California notary and witness rules automatically:
California bill of sale — FAQ
Is a bill of sale required in California?
In California, a separate bill of sale is not required. A bill of sale is optional. The DMV's REG 135 can stand in for the owner's release-of-ownership signature on the title.
Does a California bill of sale need to be notarized?
No. California's registration manual states a bill of sale is not required to be notarized or witnessed.
Do I need a witness for a bill of sale in California?
No. California does not require witnesses for a standard private bill of sale.
How do I transfer a vehicle title in California?
Seller signs the title over to the buyer; the buyer submits the title (or REG 135) and applies for transfer within 10 days. Titling and registration in California are handled by the California Department of Motor Vehicles (DMV).
Is a bill of sale proof of ownership?
Generally no. For titled property like a car or boat, the title is what proves ownership. A bill of sale proves that a sale happened and records the price, date, and terms — it supports the title transfer but does not replace it. For untitled property (furniture, equipment, electronics), the signed bill of sale is usually the main proof of ownership.