What an auto purchase order is and why you need one
An auto purchase order is a written agreement between you and a dealer that locks in the price, terms, and conditions of a vehicle sale before you sign the final paperwork. It is not the same as a sales contract — it comes before that, and it protects you by documenting what was promised before either side can change their mind.
The purchase order typically includes the vehicle identification number (VIN), the agreed price, what trade-in allowance you are receiving (if any), what dealer-installed options are included, the financing terms if the dealer is arranging the loan, and any warranties or service packages. Once both you and the dealer sign it, the dealer cannot add fees, change the price, or remove promised items without your written consent.
Without a purchase order, a dealer can show you a vehicle at one price, take your trade-in keys, and then present you with a final contract that includes thousands in additional fees, a higher price, or different terms. A purchase order creates a paper trail that makes that harder to do and gives you grounds to walk away if the final contract does not match what you signed.
Key Takeaways
- A purchase order is a binding written agreement that comes before the final sales contract and locks in price, trade-in value, and included options.
- The purchase order should list the VIN, final price, trade-in allowance, financing terms, and any dealer-installed items or warranties you negotiated.
- Both you and the dealer must sign the purchase order, and either side can usually back out before the final contract is signed, though penalties may explore.
- The final sales contract should match the purchase order exactly — if it does not, you have the right to refuse to sign and walk away.
- Dealers are not required to use a purchase order, but requesting one in writing before you negotiate puts you in a stronger position.
What information must be on the purchase order
The purchase order should be specific enough that you could hand it to another dealer and they would know exactly what vehicle and deal you are describing. Start with the VIN — this is the 17-character code that identifies the exact car, truck, or SUV on the lot. The purchase order should also include the year, make, model, color, mileage, and any factory options that came with the vehicle (leather seats, sunroof, all-wheel drive, etc.).
The price section must show the base vehicle price, any dealer-installed add-ons and their cost, the trade-in allowance (if you are trading in a vehicle), and the final out-the-door price. "Out-the-door" means the total amount you will pay, including taxes, registration fees, and dealer fees. Some dealers list these separately; others roll them into one number. Either way, the purchase order should show what the total is.
If the dealer is arranging financing, the purchase order should state the loan amount, the interest rate (or that the rate is pending lender approval), the term in months, and the monthly payment. If you are paying cash or bringing your own financing, that should be stated too. The purchase order should also list any warranties, service plans, or gap insurance the dealer is including, along with their cost.
How to request a purchase order from the dealer
Ask for a purchase order in writing — either by email or by asking the salesperson to write it down — before you hand over your keys for a trade-in appraisal or sign anything. Saying it out loud is not enough; dealers can claim they did not hear you or misunderstood. A written request creates a record.
If the dealer resists or says they do not use purchase orders, that is a red flag. Most dealers use them routinely. You can say: "I want a written purchase order that shows the VIN, the price we agreed on, my trade-in value, and the out-the-door total before I sign any contract." If they still refuse, you can walk to another dealer — this is a normal request and a dealer who will not honor it is signaling that they plan to change terms later.
Once the salesperson writes up the purchase order, read it carefully before signing. Check that the VIN matches the vehicle you looked at, the price matches what you negotiated, and the trade-in value is what they quoted. If anything is wrong, ask them to correct it and initial the change. Do not sign a purchase order with blank spaces or with "to be determined" or "TBD" in the price or trade-in fields.
What happens between the purchase order and the final contract
After you sign the purchase order, the dealer typically has it reviewed by their finance manager or sales manager. This is when they may discover that the trade-in vehicle is worth less than they thought, or that the financing terms they quoted are not available, or that they made an error in calculating the price. If any of these things happen, the dealer may contact you to renegotiate.
You are not obligated to accept changes. If the dealer says the trade-in is worth $2,000 less than they promised, you can refuse and ask them to honor the original purchase order. If they will not, you can walk away — the purchase order gives you that right. Some dealers will ask you to sign a new purchase order with revised terms; if you do, you are agreeing to the new deal.
The time between purchase order and final contract is usually 24 to 48 hours. During this window, the dealer is arranging financing, running a title check on your trade-in, and preparing the paperwork. When you return to sign the final contract, it should match the purchase order line for line. If it does not, you have the right to refuse to sign.
Comparing the final contract to the purchase order
Before you sign the final sales contract, print out or pull up the purchase order on your phone and compare them side by side. Check the VIN, the vehicle price, the trade-in allowance, the financing terms, and the out-the-door total. Look for new line items — dealer documentation fees, paint protection, fabric protection, extended warranties — that were not on the purchase order. These are common places dealers add cost.
If the final contract includes fees or charges that were not on the purchase order, ask the dealer to remove them or to explain why they were added. If they say it is standard or required, ask to see the purchase order again and point out that you did not agree to it. You can refuse to sign a contract that does not match the purchase order.
Pay special attention to the financing section. If the purchase order said the interest rate was 4.5 percent and the contract says 5.2 percent, that is a material change. The dealer may say the lender changed the rate, but you have the right to reject the new terms and either walk away or ask the dealer to buy down the rate to match the purchase order.
When you can back out and what it costs
Both you and the dealer can usually back out of a purchase order before the final contract is signed. If you change your mind, the dealer may keep a deposit (usually a few hundred dollars) as a cancellation fee, depending on what the purchase order says. Some purchase orders state that the deposit is non-refundable if you cancel; others say it is refundable. Read this section carefully before you sign.
If the dealer backs out — for example, because they cannot arrange financing or because the trade-in appraisal came in much lower — you are may have access to to your deposit back. Some dealers will offer you a credit toward another vehicle instead; that is their choice, but you have the right to ask for a refund.
Once you sign the final sales contract, backing out is much harder and usually costs you more. Most sales contracts include a cooling-off period of a few days (the length varies by state), during which you can cancel and get your deposit back. After that window closes, canceling usually means losing your deposit and possibly owing the dealer money if they have already sold your trade-in or incurred costs on your behalf.
Red flags that mean you should not sign
Do not sign a purchase order if the VIN field is blank or if the dealer says they will "fill it in later." The VIN is how you know you are buying the specific vehicle you looked at. If it is blank, the dealer could substitute a different car.
Do not sign if the price field says "to be determined" or "subject to manager approval" or if there are blank lines where numbers should be. A purchase order with blanks is not an agreement — it is a template, and the dealer can fill in whatever they want after you leave.
Do not sign if the dealer will not let you keep a copy. You need a copy to compare against the final contract. If the dealer says they will email it to you later, ask them to print it and give it to you before you leave the lot.
Do not sign if the purchase order includes language saying you waive your right to a cooling-off period or that you agree to binding arbitration instead of going to court. These clauses limit your options if something goes wrong.
Frequently Asked Questions
Is a purchase order the same as a sales contract?
No. A purchase order comes first and is usually less formal — it is an agreement to the terms before the final paperwork is drawn up. The sales contract is the legal document you sign at the end and includes additional disclosures and terms. The purchase order protects you by locking in what was promised before the sales contract is written.
Can the dealer change the price after I sign the purchase order?
Not without your written consent. If the dealer tries to charge you more at the final contract stage, you can refuse to sign and walk away. The purchase order is binding on both sides — if the dealer wants to change it, they have to ask you to sign a new one.
What if the dealer says the financing fell through?
If the dealer arranged the financing and it falls through, they cannot force you to accept different terms. You can ask them to find another lender at the same rate, to buy down the rate themselves, or to let you walk away and keep your deposit. What you are not required to do is accept a higher interest rate than what the purchase order promised.
Do I have to use the dealer's financing if I sign a purchase order?
No. If you bring your own financing (a loan from your bank or credit union), the purchase order should state that. The dealer cannot force you to use their lender. However, some dealers offer incentives for using their financing, so compare the total cost of both options before you decide.
What should I do if the purchase order and the final contract do not match?
Do not sign the final contract. Point out the differences to the dealer and ask them to correct the contract to match the purchase order. If they will not, you can refuse to sign and ask for your deposit back. You are not obligated to accept terms that differ from what you agreed to in writing.