What a California bill of sale is and why you need one

A bill of sale is a written record that proves you bought or sold a vehicle. In California, it documents the transfer of ownership between you and the other party—the seller if you're buying, or the buyer if you're selling. The state doesn't require a bill of sale to register a vehicle, but it protects both of you by creating a paper trail of the transaction.

Without a bill of sale, disputes can arise about the sale price, the condition of the vehicle at handover, or who owned it on a specific date. If something goes wrong after the sale—the buyer doesn't pay, the seller doesn't transfer the title, or the vehicle is involved in an accident—a bill of sale is your evidence of what was agreed and when.

California's Department of Motor Vehicles (DMV) provides an official form, but you can also write your own as long as it includes the required information. Either way, both the buyer and seller should keep a signed copy.

Key Takeaways

  • California's official bill of sale form is the REG 135, available free from the DMV website or in person at any DMV office.
  • A bill of sale must include the vehicle identification number (VIN), the sale price, the date of sale, and the signatures of both buyer and seller.
  • You can use the DMV form or write your own bill of sale, as long as it contains all required information and is signed by both parties.
  • The bill of sale protects you if disputes arise after the sale, such as payment issues or questions about vehicle condition or ownership date.
  • Keep your signed copy of the bill of sale with your vehicle records; it may be needed when you register the vehicle or if you later sell it.

The official California DMV bill of sale form

The California DMV publishes form REG 135, titled "process for Title or Registration." This form serves as both an process and a bill of sale. You can read it from the DMV website (dmv.ca.gov) or pick up a printed copy at any DMV office, county assessor's office, or some vehicle dealerships.

The REG 135 includes spaces for the vehicle's VIN, make, model, year, and odometer reading. It also has sections for the seller's and buyer's names, addresses, and signatures. The form asks for the sale price, which is important because California uses it to calculate registration fees and to verify the transaction is legitimate.

If you're buying a used vehicle from a private seller, the seller should complete and sign the bill of sale section before you hand over money. If you're selling, you complete your portion and sign. Both parties keep a copy.

What information must be on a California bill of sale

Whether you use the DMV form or write your own, the bill of sale must include the vehicle's VIN (found on the dashboard, driver's door jamb, or title document). It must also show the vehicle's make, model, and year. Without the VIN, the document is incomplete and won't protect you if a dispute arises.

The sale price must be stated clearly. This is not optional—California law requires it. The price is used to calculate registration and transfer fees, and it's also evidence of the transaction's legitimacy. If you leave the price blank or write "as is," the DMV may reject the document or delay processing.

Include the date of sale, the seller's full name and address, and the buyer's full name and address. Both parties must sign and print their names. If the vehicle has a lien (a loan against it), the lienholder's name should also appear. Some forms ask for the odometer reading at the time of sale—include this if the form has a space for it, as it protects against odometer fraud.

How to fill out and sign the bill of sale

If you're using the REG 135, print it and fill in all required fields in black or blue ink. Write clearly and use the vehicle's legal name as it appears on the title—not a nickname or shortened version. The seller completes their section first, signs, and dates it. The buyer then completes their section, signs, and dates it.

Both parties should sign in front of each other if possible, though California does not require a notary or witness for a bill of sale. However, having a witness present adds an extra layer of protection if the transaction is later questioned. Some sellers and buyers choose to have the bill of sale notarized, which is optional but can be useful if the vehicle is expensive or the buyer is financing it through a lender.

Make copies before either party leaves. Each person should keep at least one signed original or certified copy. The buyer will need their copy when registering the vehicle with the DMV. The seller should keep their copy as proof they no longer own the vehicle, in case it's involved in an accident or traffic violation after the sale.

When to use a bill of sale in California

Use a bill of sale whenever you buy or sell a vehicle privately—that is, between individuals rather than through a dealership. Dealerships typically handle their own paperwork and provide their own bill of sale or sales agreement, which serves the same purpose.

A bill of sale is especially important if the vehicle is being financed. Lenders often require one as proof of the purchase price and the date of ownership transfer. If you're buying a vehicle with a loan against it, the bill of sale documents the sale and helps clarify who is responsible for paying off that loan.

You should also use a bill of sale if you're transferring a vehicle to a family member, even as a gift. In that case, write "gift" or "$0" in the price field, but still complete all other information. This protects both of you by creating a record of when ownership changed hands.

What happens after you sign the bill of sale

Once both parties have signed, the buyer should take their copy to the DMV along with the title (if the seller has already signed it over) or the seller's process for title transfer. The buyer has 10 days from the date of purchase to register the vehicle in their name. If they don't, they may face late fees or penalties.

The seller should sign the back of the title document (the official certificate of ownership) and give it to the buyer. The bill of sale and the signed title together prove the transfer of ownership. The seller should keep their copy of the bill of sale as proof they no longer own the vehicle.

If there's a delay in registration or if the buyer doesn't register the vehicle, the seller remains the registered owner in the DMV's records. This is why the bill of sale is important—it shows you sold the vehicle on a specific date, even if the buyer hasn't yet registered it in their name.

Writing your own bill of sale instead of using the DMV form

You don't have to use the official REG 135. You can write a bill of sale on plain paper as long as it includes all required information: the VIN, make, model, year, sale price, date, seller's name and address, buyer's name and address, and both signatures. Some people use a template from an online source or write one from scratch.

If you write your own, be specific and clear. Avoid vague language like "sold for a fair price" or "as is." State the exact price in dollars. If the vehicle has known defects or damage, you can note that in the bill of sale—for example, "sold with a dent in the driver's door" or "transmission has a known noise." This protects the seller by documenting that the buyer knew about the issue at the time of purchase.

Handwritten bills of sale are legal in California as long as they're legible and signed by both parties. However, a typed or printed version is clearer and less likely to be questioned later. Keep the original signed copy, not just a photocopy or photo on your phone.

Frequently Asked Questions

Do I need a notary to sign a bill of sale in California?

No, California does not require a notary for a bill of sale. Both parties can sign without a witness or notary present. However, having a notary stamp the document adds credibility if the transaction is later disputed, especially for expensive vehicles. It costs $10 to $20 and takes a few minutes at a bank, UPS store, or notary public's office.

What if the seller won't give me a bill of sale?

You should not complete the purchase without one. A bill of sale is your only proof of the transaction and the sale price. If the seller refuses, it's a red flag—they may be hiding something about the vehicle's history or ownership. Walk away from the deal or insist on a bill of sale before handing over money.

Can I use a bill of sale if the vehicle still has a loan on it?

Yes, but the lienholder's name must appear on the bill of sale and the title. The seller is responsible for paying off the loan before transferring the title to you. If they don't, you could inherit the debt. Always check the title to see if there's a lien, and confirm with the lender that the loan will be paid off at the time of sale.

How long should I keep my copy of the bill of sale?

Keep it as long as you own the vehicle, and for several years after you sell it. If you're the seller, keep your copy for at least three to five years as proof you no longer own the vehicle. If you're the buyer, keep it with your vehicle records and title. You may need it if you sell the vehicle later or if there's a dispute about ownership.

What if I lost my bill of sale?

If you're the buyer, you can request a copy from the seller. If you're the seller and the buyer lost theirs, you can provide a copy of your signed original. If both copies are lost, you can contact the DMV to request a record of the registration transfer, though this may take time. This is why keeping your bill of sale in a safe place is important.