What a California bill of sale is and why the DMV cares about it

A bill of sale is a written record that you and the buyer (or seller) sign to document the transfer of a vehicle. In California, it is not a legal requirement to use a specific state form, but the DMV will ask for proof of the sale price and the date of transfer when you register the vehicle in the new owner's name. Without a bill of sale, you have no documented proof of what happened, and disputes over price, condition, or ownership become much harder to resolve.

The bill of sale protects both you and the other party. If you are selling, it proves you no longer own the car on a specific date. If you are buying, it proves what you paid and that the seller agreed to the sale. The DMV uses the sale price to calculate sales tax for the buyer, so an accurate bill of sale matters for their paperwork, not just yours.

California does not mandate a single form, but the state provides one: the REG 135, also called the "process for Title or Registration." You can also write your own bill of sale as long as it includes the required information. Many people use a straightforward template or write one by hand, and the DMV will accept it as long as the essential details are there.

Key Takeaways

  • California does not require a specific bill of sale form, but the DMV's REG 135 is the official option and available free on the California DMV website.
  • A bill of sale must include the vehicle identification number (VIN), the sale price, the date of sale, and the signatures of both the seller and buyer to be valid.
  • The buyer will need the bill of sale to register the vehicle and calculate sales tax; the seller should keep a copy for their records.
  • You can write your own bill of sale by hand or use a template, as long as it contains all required information and is signed by both parties.
  • A notarized bill of sale is not required by California law, but notarization adds legal weight if a dispute arises later.

What information must be on the bill of sale

The bill of sale must include the vehicle's VIN (vehicle identification number), which is a 17-character code unique to that car. You will find it on the dashboard on the driver's side, on the vehicle registration, or on the title document. Without the VIN, the DMV cannot match the bill of sale to the correct vehicle, and the registration will be delayed.

You also need the sale price — the actual amount paid, not a guessed or reduced figure. The buyer will use this number to calculate sales tax, and the DMV may ask for proof if the price seems unusually low. Write the price in both numbers and words to avoid confusion (for example, "$5,000" and "Five thousand dollars").

The bill of sale must show the date of sale, the seller's name and address, and the buyer's 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. The seller should note the vehicle's condition and mileage at the time of sale, though this is not strictly required by the DMV.

Using the California DMV's REG 135 form

The REG 135 is the official California bill of sale and title process combined into one document. You can read it free from the California DMV website (dmv.ca.gov) or pick up a copy at any DMV office. The form has sections for the seller's information, the buyer's information, the vehicle details, and the sale price.

To fill it out, start with Section 1 (seller information) and Section 2 (buyer information). Then move to the vehicle description section and enter the VIN, the year, make, and model. In the "Sale Price" field, write the amount paid. Both the seller and buyer must sign and date the form in the designated spaces. Do not leave any required field blank, or the DMV will return it and delay the registration.

Once completed, the seller keeps one copy and gives the original to the buyer. The buyer will submit the REG 135 along with the vehicle title and other registration documents to the DMV. If you are buying the car, ask the seller for a signed copy before you leave with the vehicle, so you have proof of purchase in case something goes wrong during the registration process.

Writing your own bill of sale instead of using a form

If you prefer not to use the REG 135, you can write a bill of sale on plain paper or use a template from a reliable source. The document does not need to be fancy or printed on special paper. Handwritten bills of sale are legal in California as long as they contain all the required information and are signed by both parties.

Start with a heading like "Bill of Sale" at the top. Then write out the seller's full name and address, the buyer's full name and address, and the date of the sale. Include the vehicle's VIN, year, make, model, and color. State the sale price in both numbers and words. Add a line that says something like "The seller hereby sells the above vehicle to the buyer for the price stated above," and have both parties sign and print their names below.

Keep the language straightforward and clear. You do not need legal jargon for the DMV to accept it. What matters is that the essential facts are there and both parties have signed. If the vehicle has an outstanding loan, mention the lienholder's name and that the lien will be paid off before or after the sale. This prevents confusion later if the buyer tries to register the car and discovers a lien still attached.

What happens to the bill of sale after the sale

The buyer must bring the bill of sale to the DMV when they register the vehicle in their name. The DMV will use it to verify the sale price, calculate sales tax, and confirm that the transfer is legitimate. The buyer should submit the bill of sale along with the vehicle title, proof of insurance, and a completed registration process (usually the REG 135 or REG 343).

The seller should keep a copy of the signed bill of sale for at least three to five years. This protects you if the buyer later claims you misrepresented the vehicle's condition or if there is a dispute about the sale. If the vehicle is involved in an accident or crime after the sale, having a dated, signed bill of sale proves you no longer owned it at that time.

If you are the buyer and the seller does not give you a signed copy, ask for one before you hand over money. Do not leave the lot without proof of the sale in writing. If the seller refuses to sign a bill of sale, that is a red flag — it suggests they may not be the legal owner or may be hiding something about the vehicle's history.

Notarization and when you might want it

California law does not require a bill of sale to be notarized. A notary's signature does not make the document more valid in the eyes of the DMV. However, notarization does add a layer of legal protection if a dispute arises later, because a notary has verified the identity of both parties and witnessed their signatures.

You might consider notarization if the vehicle is expensive, if you are selling to someone you do not know well, or if there is any uncertainty about the buyer's identity or intent. A notary public can be found at most banks, UPS stores, and some DMV offices. The cost is usually between $10 and $25 per signature. Both the seller and buyer should have their signatures notarized for maximum protection.

If you do get the bill of sale notarized, make sure the notary writes their commission number, the date, and their seal on the document. Give the original notarized copy to the buyer and keep a copy for yourself. The DMV will accept a notarized bill of sale just as readily as an unnotarized one, but it carries more weight if you ever need to prove the sale in court.

Common mistakes to avoid when writing a bill of sale

The most common mistake is leaving the VIN blank or writing it incorrectly. Double-check the VIN against the title or registration before you write it on the bill of sale. A wrong VIN will cause the DMV to reject the document and delay the buyer's registration by weeks.

Another mistake is writing a sale price that does not match what was actually paid. If you agree on $8,000 but write $5,000 to reduce the buyer's tax burden, you are committing tax fraud. The DMV cross-checks sale prices against market value, and unusually low prices trigger audits. Be honest about the price, even if it is higher than you expected.

Do not sign the bill of sale unless both parties are present and agree to the terms. If you sign it early and the buyer changes their mind or disputes the price later, you have no recourse. Sign it only when the money has changed hands and both of you are ready to finalize the sale. Make sure both the seller and buyer sign — a bill of sale signed by only one party is not valid.

Frequently Asked Questions

Can I use a bill of sale from a template online?

Yes, as long as the template includes all required information: VIN, sale price, date, seller and buyer names and addresses, and signatures from both parties. Many free templates are available online and are accepted by the DMV. Just make sure you fill in every blank and that both parties sign before the buyer takes the vehicle.

What if I lost the bill of sale after the sale?

If you are the seller, you can ask the buyer for a copy. If you are the buyer and lost your copy, you can request a duplicate from the seller or contact the DMV to see if they have a record of the registration. The DMV keeps copies of documents submitted during registration, so you may be able to get a certified copy for a small fee.

Do I need a bill of sale if I am trading in my car at a dealership?

No. Dealerships handle their own paperwork and do not use a standard bill of sale. They will give you a receipt and handle the title transfer themselves. You do not need to create a bill of sale for a trade-in.

What if the seller will not sign the bill of sale?

Do not buy the car. A seller who refuses to sign a bill of sale is a major warning sign. It suggests they may not be the legal owner, the vehicle may have a hidden lien, or they are trying to hide something. Walk away and find another vehicle.

Is a bill of sale the same as a title?

No. A bill of sale is proof of the sale and the price paid. The title is the legal document that proves ownership. The buyer will need both the bill of sale and the title to register the vehicle with the DMV. The seller transfers the title by signing the back of it; the bill of sale is a separate document.