Can I sell a car on someone else's behalf?
You can only sell a car on someone else’s behalf in specific situations. Read our article to find out exactly when and how you can sell a car on someone else’s behalf.
Words by: Nimisha Jain
Published on 29 July 2026 | 0 min read
Each car selling platform has its own rules when it comes to selling a car on someone else’s behalf.
If you’re a private seller looking to sell a car for someone else through Autotrader, you can only do so if they’re a member of your family or household. To prove this, you’ll either have to show that:
- you share an address with them
- you share a family name with
Note: on Autotrader, selling a vehicle on behalf of someone outside your family would be considered a trade sale. It's against our Terms and Conditions (section 13.2) and UK law to sell a vehicle as a private seller when it should be a trade sale.
How to sell a car on someone else’s behalf on Autotrader
First of all, make sure you’ve got the car owner’s permission first to sell the car on their behalf. Once you’ve got their permission, you can sell the car by either:
Registering the account in the owner’s name
With their permission, you set up the account using their details and place the advert. If Autotrader needs to confirm anything, the owner must be available for checks. We can only discuss the account with the named account holder for security reasons, so please bear this in mind if you choose this option.
Or,
Registering the account in your own name
You can create the listing under your details, but you should be transparent. Clearly state in the advert that you’re selling on behalf of someone else and that you are not the owner. Both options work - just make sure you’re honest in the listing so buyers know the situation
What document do I need to sell someone else’s car?
• The owner’s V5C logbook showing their name • Service history book • MOT certificates • Proof of ID such as a driving licence or passport for you and the car’s owner • Any receipts or paperwork about maintenance or fixes
Is it easy to sell a car on someone else’s behalf?
Buyers might hesitate to buy the car if the paperwork isn’t clear or if they’re unsure that you have the right to sell – this is where having a letter of intent will help. Also, if there are any mistakes with documents, then it can cause delays or even cancel the sale, so make sure you and the owner of the car double-check all documents. You may also need to discuss the lowest price the owner is willing to accept – having this conversation beforehand can help avoid any confusion later.