What You Need to Do When You Sell or Buy a Car in California

When you sell a vehicle in California, both the seller and buyer have specific steps to complete with the DMV. The seller must report the sale within five days, and the buyer must register the vehicle in their name. If you do not report the sale, you remain liable for tickets, tolls, and accidents involving that vehicle — even after it leaves your possession.

The process differs slightly depending on whether you are selling to a private party, trading in at a dealership, or buying from someone else. Dealerships handle most of the paperwork automatically, but private sales require you to file forms yourself. Understanding which documents you need and where to submit them will prevent delays and protect you from future liability.

Key Takeaways

  • Sellers must report the sale to the DMV within five days using Form REG 138 (Notice of Transfer and Release of Liability) to avoid remaining liable for the vehicle.
  • Buyers must complete the registration process within 10 days of purchase, which includes submitting the title, proof of insurance, and a completed process.
  • You can file the Notice of Transfer online through the DMV website, by mail, or in person at a DMV office — online is fastest and costs nothing.
  • If you sell to a dealership, they handle the paperwork; if you sell privately, you must file the forms yourself or the sale is not officially recorded.
  • Keeping proof that you reported the sale protects you if the new owner gets a ticket or is involved in an accident after the sale date.

How Sellers Report a Sale to the DMV

As the seller, your main responsibility is to file a Notice of Transfer and Release of Liability (Form REG 138) with the California DMV. This form tells the state that you no longer own the vehicle and removes you from liability for anything that happens to it after the sale. You must file this within five days of the sale, even if the buyer has not yet registered the vehicle in their name.

You have three ways to file: online through the DMV website (fastest, no fee), by mail to your local DMV office, or in person. To file online, you will need the vehicle's license plate number or VIN, the buyer's name and address, and the sale date. The DMV will email you a confirmation, which you should save as proof that you reported the sale on time. If you mail the form, keep a copy for your records and consider using certified mail so you have proof of delivery.

If you sell the vehicle to a dealership, the dealer files the paperwork for you — you do not need to file Form REG 138 yourself. However, if you sell to a private buyer, you must file it yourself. Failing to report the sale means you stay on the title and remain responsible for registration fees, parking tickets, and toll violations the new owner incurs.

What Buyers Need to Do to Register the Vehicle

As the buyer, you must complete the registration process within 10 days of purchase. Start by gathering the documents you will need: the signed title (also called the pink slip), a bill of sale, proof of California insurance, and a completed process for Title or Registration (Form REG 343). If the vehicle is financed, your lender will need to be listed on the title.

You can register the vehicle online through the DMV website if the title is already in your name and you have all required documents scanned. For most private sales, however, you will need to visit a DMV office or use a DMV-authorized service. Bring the original title signed by the seller, your proof of insurance, and your identification. The DMV will process your process, issue new registration documents, and send you new license plates or a registration sticker within two to three weeks.

If you buy from a dealership, the dealer typically handles the registration paperwork and submits it to the DMV on your behalf. You will receive your registration documents by mail. If you buy privately and do not register within 10 days, you will owe a late fee when you eventually register, and you cannot legally drive the vehicle on public roads.

Documents You Need for a Private Sale

A private sale requires more paperwork than a dealership transaction because there is no middleman to handle the filing. The seller needs the vehicle's title (the pink slip), which must be signed and dated by the seller in the presence of the buyer or a notary. The buyer needs proof of insurance before they can register the vehicle — California requires all registered vehicles to have active insurance.

Both parties should complete a bill of sale, which is a straightforward document showing the sale price, date, vehicle details, and signatures of both buyer and seller. While California does not legally require a bill of sale, it protects both parties by creating a record of the transaction. You can use the DMV's bill of sale form or a straightforward written agreement. The buyer will also need to bring a completed process for Title or Registration (Form REG 343) when registering at the DMV.

If the vehicle has a lien (meaning it is financed), the title will show the lender's name. The seller cannot transfer a liened vehicle without the lender's permission, and the lender must release the lien before the buyer can register it. This usually happens automatically when the seller pays off the loan, but the buyer should verify that the lien is released before completing the purchase.

Timing and Fees for Ownership Transfer

The seller's important date is five days from the sale date to file the Notice of Transfer. The buyer's important date is 10 days from purchase to register the vehicle. These are firm important date — missing them results in penalties. The seller who does not file within five days remains liable for the vehicle; the buyer who does not register within 10 days faces a late registration fee and cannot legally operate the vehicle.

Registration fees vary based on the vehicle's value and weight. A typical passenger car registration costs between $250 and $350 for the first year, though this includes the title transfer fee. If you register late, you will owe the registration fee plus a penalty. The DMV charges no fee for filing the Notice of Transfer online, but mailing it costs the price of postage. If you use a DMV-authorized service or a dealership to handle registration, they may charge a service fee on top of the DMV's official fees.

Processing times depend on how you file. Online registration typically shows confirmation within minutes, though your physical registration documents arrive by mail in two to three weeks. In-person registration at a DMV office can be completed the same day, but wait times vary by location. Mail-in registration takes one to two weeks after the DMV receives your documents.

What Happens If You Do Not Report the Sale

If you are the seller and do not file the Notice of Transfer within five days, you remain the registered owner in the DMV's system. This means you are liable for registration renewal fees, parking tickets, toll violations, and traffic citations the new owner receives. If the vehicle is involved in an accident and the new owner does not have insurance, you could be held responsible. Even if you have a bill of sale proving you sold the car, the DMV's records still show you as the owner until you file the notice.

If you are the buyer and do not register within 10 days, you cannot legally drive the vehicle on public roads. If you are stopped by law enforcement, you will be cited for driving an unregistered vehicle. You will also owe a late registration penalty when you eventually register. Additionally, your insurance may not cover an unregistered vehicle, leaving you financially exposed if you are in an accident.

The best protection is to file when ready. Sellers should file the Notice of Transfer online the day of the sale and keep the confirmation email. Buyers should gather all documents and visit the DMV or file online within a few days of purchase, not waiting until day 10.

Using DMV-Authorized Services and Dealerships

If you do not want to handle the paperwork yourself, you can use a DMV-authorized service or have a dealership process the transfer. These services charge a fee — typically $50 to $150 — but they handle all the filing and may support important date are met. They are useful if you are buying or selling out of state, if the title has complications, or if you straightforward prefer not to visit the DMV.

Dealerships automatically process ownership transfers for both buyers and sellers. When you trade in a vehicle, the dealership files the Notice of Transfer for you. When you buy from a dealership, they register the vehicle in your name and submit all paperwork to the DMV. You will receive your registration documents by mail. This is the simplest route because the dealership has experience with the process and handles errors or missing documents.

DMV-authorized services (sometimes called "title services" or "registration services") operate independently and can file paperwork on your behalf. You provide them with the documents and payment, and they submit everything to the DMV. They are particularly useful for private sales where the buyer and seller live far apart or for situations where the title has a lien or other complications. Check the DMV website for a list of authorized services in your area.

Frequently Asked Questions

What if I sell my car but the buyer never registers it?

If you file the Notice of Transfer within five days, you are released from liability even if the buyer never registers the vehicle. The notice tells the DMV that you no longer own it, so any tickets or violations go to the buyer, not you. Keep your confirmation email as proof you filed on time.

Can I register a vehicle I bought without the seller's signature on the title?

No. The title must be signed by the seller and dated. If the seller refuses to sign or has already sold the vehicle to someone else, you cannot register it. If you have already paid for the vehicle, you will need to pursue the matter through small claims court or contact law enforcement if you believe fraud occurred.

Do I need to notify my insurance company when I buy or sell a vehicle?

Yes. If you are selling, notify your insurer so they can cancel or transfer your policy. If you are buying, you must have insurance before you register the vehicle — the DMV requires proof of insurance as part of the registration process. Contact your insurance company before you visit the DMV.

What if the vehicle has a loan against it?

The lender's name appears on the title. The seller cannot transfer the vehicle until the loan is paid off and the lender releases the lien. Once the loan is paid, the lender sends a lien release document to the seller, who then signs the title over to the buyer. The buyer should verify that the lien release is included before completing the purchase.

How long does it take to get new license plates after I register?

The DMV mails registration documents and license plates within two to three weeks of processing your process. If you need plates when ready, some DMV offices issue temporary registration that allows you to drive while you wait for permanent plates. Ask about this option when you register.