What a Colorado bill of sale does and when you need one
A bill of sale is a written record that you and the other person sign to show that a car has changed hands. In Colorado, a bill of sale documents who owned the car, who owns it now, the sale price, and the date of the sale. It is not the same as a title — the title is the state document that proves ownership — but a bill of sale is the paper trail that shows how ownership moved from one person to another.
Colorado law does not require a bill of sale to transfer a car between private parties, but you should create one anyway. If something goes wrong later — the buyer claims the car was damaged before the sale, the seller tries to say they never sold it, or the state questions who owned the car on a particular date — a signed bill of sale is the evidence that protects both of you. It also creates a record of the sale price, which matters for taxes and for proving you are not hiding income or a gift.
You need a bill of sale whenever you sell or buy a car from another person in Colorado, not from a dealership. Dealerships handle their own paperwork. If you are giving a car to a family member, you should still use one — it shows the state that the transfer was intentional and documented, not a mistake or a loan.
Key Takeaways
- A Colorado bill of sale is a written agreement between buyer and seller that documents the car's details, sale price, and the date of transfer, and both parties must sign it.
- Colorado does not legally require a bill of sale for private car sales, but creating one protects both the buyer and seller if disputes arise later.
- The bill of sale should include the vehicle identification number (VIN), make, model, year, odometer reading, sale price, and the printed names and signatures of both parties.
- You can use a straightforward written document, a form from the Colorado Parks and Wildlife website, or a template from a title service — all are equally valid as long as both parties sign.
- Keep a copy of the signed bill of sale with your car records; the buyer will need their copy when they register the car with the Colorado Department of Revenue.
What information to include on a Colorado bill of sale
The bill of sale should contain the vehicle identification number (VIN), which is a 17-character code stamped on the car and listed on the title. Include the year, make, and model of the car. Write down the odometer reading on the day of sale — this is a legal requirement in Colorado and helps prevent odometer fraud. List the sale price in dollars, even if the car is a gift (write "gift" or "$0" but still document it).
Add the full legal names, addresses, and signatures of both the seller and the buyer. Include the date the sale took place. If the car has a lien on it — meaning a bank or lender still owns part of it — note that on the bill of sale and include the lender's name. The buyer needs to know before they buy that the car is not fully paid off.
You can also note the condition of the car ("as-is," "good condition," "needs repairs") and any promises the seller is making about the car's history or mechanical state. This protects the buyer if the seller later claims they never said the transmission was broken, and it protects the seller if the buyer later claims the car was supposed to be in perfect condition.
Where to find a bill of sale form in Colorado
Colorado Parks and Wildlife publishes a bill of sale form on its website that you can read and print for free. Search for "Colorado bill of sale form" and look for the official state form — it is a straightforward one-page document with blanks for all the required information. You do not have to use the state form; any written document that both parties sign and that includes the required information is legally valid.
You can also write your own bill of sale by hand or type one up yourself. The form does not have to be fancy or use legal language. As long as it shows who sold the car, who bought it, what car it was, how much it cost, and when the sale happened, and both parties have signed it, it will hold up if there is ever a dispute.
Title services and online legal document sites also offer bill of sale templates. These are usually free or cost a few dollars. The advantage of using a template is that it reminds you what to include and is formatted in a way that looks official, which can be helpful if you ever need to show it to a lender or the state.
How to fill out and sign the bill of sale
Print or write out the form. Fill in all the blanks with accurate information — the VIN from the title or the car itself, the odometer reading from the dashboard, the sale price that you and the buyer agreed on, and the date of the sale. Write out numbers in words as well as figures (for example, "Five Thousand Dollars ($5,000)") so there is no confusion later.
Both the seller and the buyer should sign and print their names on the form. It is best if both people are present when you sign, so you can both verify that the information is correct and that you both agree to the sale. If that is not possible, the seller can sign first and give the form to the buyer to sign, but having both signatures on the same document is stronger evidence.
Do not sign the title itself until you have a signed bill of sale. The bill of sale comes first — it is the record of the agreement. The title transfer happens after, when the buyer takes the signed title to the Colorado Department of Revenue to register the car in their name.
What happens to the bill of sale after the sale
Keep a copy for your records. If you are the seller, store it with your car maintenance records or financial documents. If you are the buyer, keep it with the title and registration. You may need it later to prove when you bought the car, what you paid for it, or what condition it was in when you took ownership.
The buyer will need their copy of the signed bill of sale when they go to the Colorado Department of Revenue to register the car. The state does not require you to send the bill of sale to them, but the buyer should bring it along with the title, proof of insurance, and proof of residency. If there is ever a dispute about the sale — for example, if the seller claims the buyer owes them money, or if the buyer claims the seller misrepresented the car — the bill of sale is the document that shows what was actually agreed to.
Transferring the title after the bill of sale is signed
Once both parties have signed the bill of sale, the seller must sign the back of the title. The title is the official state document; the bill of sale is the record of the agreement, but the title is what the state uses to track ownership. The seller signs the title to release ownership, and the buyer takes the signed title to the Colorado Department of Revenue to register the car in their name.
The buyer should complete this step within a reasonable time — usually within 10 days of the sale, though Colorado does not set a strict important date. Waiting too long can cause problems if the seller is still listed as the owner and the car is involved in an accident or gets a parking ticket. The bill of sale shows when the sale actually happened, so it protects the seller even if the buyer delays registering the car.
The Colorado Department of Revenue charges a fee to transfer the title and register the car. The buyer pays this fee, not the seller. The buyer will also need to provide proof of insurance and proof that they live in Colorado before the state will issue a new title in their name.
Special situations: gifts, trades, and cars with liens
If you are giving a car to a family member as a gift, you still need a bill of sale. Write the sale price as "$0" or "gift," but sign and date it anyway. This shows the state that the transfer was intentional and documented. The person receiving the gift will still need to register the car and pay the registration fee, but the bill of sale proves they did not buy it and did not owe you money.
If you are trading a car as part of the sale — for example, you are selling your car and the buyer is giving you their old car in exchange — document both cars on the bill of sale. Write down the value of each car and note that the sale is a trade. This is important for tax purposes and for proving to the state what each car was worth on the day of the sale.
If the car has a lien on it, the seller cannot transfer the title until the lender releases the lien. The bill of sale should note that a lien exists and include the lender's name and contact information. The buyer should not hand over money until the seller has proof that the lien will be paid off and released. In some cases, the sale price goes directly to the lender to pay off the loan, and the lender releases the title to the buyer. The bill of sale documents this arrangement.
Frequently Asked Questions
Do I have to use the official Colorado bill of sale form?
No. Any written document that both parties sign and that includes the vehicle details, sale price, date, and both signatures is legally valid in Colorado. The official form is free and convenient, but a handwritten agreement or a template from another source works just as well.
What if I lose my copy of the bill of sale after the sale?
If you are the seller and you lose your copy, you have already signed the title and released ownership, so you are protected. If you are the buyer and you lose your copy, you still have the title in your name, which is the official proof of ownership. It is best to keep a copy, but losing it does not undo the sale.
Can I sell a car without a bill of sale in Colorado?
Colorado law does not require a bill of sale for private car sales, so technically you can sell without one. However, it is a bad idea. Without a bill of sale, there is no written record of the agreement, the price, or the date. If the buyer later claims the car was damaged before the sale or the seller claims they never agreed to sell it, there is no document to prove what actually happened.
Does the bill of sale have to be notarized?
No. Colorado does not require a bill of sale to be notarized. Both parties straightforward need to sign it in front of each other or separately, and the signatures do not need to be witnessed or certified. A notarized bill of sale is stronger evidence in court, but it is not required.
What if the buyer does not register the car right away?
The bill of sale shows when the sale actually happened, so the seller is protected even if the buyer waits weeks or months to register the car. However, the seller should not sign the title until they are sure the buyer has the money and intends to complete the purchase. Once the title is signed, the seller has released ownership, even if the buyer never registers the car.