Introduction
Selling a car on someone else's behalf is common, whether you're helping a parent, a relative abroad or a friend. UK law allows it only with the right authority and paperwork.
Here's what the process involves: what you need, how the DVLA notification works and the situations that need extra care.
Summary:
- You need the registered keeper's written authority. A signed letter of authority is the minimum. Buyers commonly insist on one.
- The V5C shows the keeper, not necessarily the owner. A buyer who purchases from a seller without the owner's authority can end up with no better title than the seller had.
- Expect to provide ID for both people. Buyers typically want ID for the keeper and the seller, the V5C and the keeper's bank details.
- Selling for someone outside your family can count as a trade sale. Autotrader says it does on its platform. Check each platform's rules.
- A registered Lasting Power of Attorney is needed if the owner has lost capacity. Signing someone else's name without authority can be a criminal offence.
- The keeper must tell the DVLA about the sale. A motor trader can do this online with the keeper's consent.
Can You Sell Someone Else's Car?
Yes, provided the person it belongs to has given clear authority. If the registered keeper is happy for you to sell, a signed letter of authority is the minimum. Motorway recommends one even for a private sale to avoid problems later.
One exception applies. If the keeper is present at the handover and you're only helping with the process online or by phone, Motorway says no extra documents are needed.
Why Authority Matters
The V5C records the registered keeper, who isn't necessarily the legal owner. A seller must have the right to sell under section 12 of the Sale of Goods Act 1979.
Under section 21, where a car is sold by someone who isn't the owner and without the owner's authority, the buyer acquires no better title than the seller had. Buyers and dealers therefore ask for proof of authority.
What You Need to Sell Someone Else's Car
The V5C: The logbook should be in the registered keeper's name. Only the registered keeper can apply for a replacement.
A signed letter of authority: The registered keeper should write and sign this.
ID for both people: Motorway asks for proof of identity for the registered keeper and the person selling, plus proof of the address on the V5C. A copy of the keeper's driving licence helps verify their signature.
Carwow says a trader or buying service may also ask for a utility bill confirming the keeper lives at the V5C address. A bank statement may also be requested as extra security.
The keeper's bank details: Payment normally goes to the registered keeper. Have their details ready.
Finance paperwork: A settlement letter is needed if finance is outstanding.
The usual extras: Service history, MOT certificate and keys.
What a Letter of Authority Should Include
There's no single required format. Carwow suggests a letter of intent covering these points:
- Permission from the owner for you to sell the vehicle
- A statement that the owner is legally entitled to sell the car
- The vehicle's make, model and registration number
- The names and addresses of both the owner and you
- Signatures from both of you, with the date
Buyers may hesitate if the paperwork isn't clear, according to Autotrader. Double-check every document with the owner, since mistakes can delay or even cancel a sale.
Agree the Terms First
Before advertising, agree where the car will be sold, the asking price, the lowest price the owner will accept and anything they want buyers to know about the car. Carwow and Autotrader both recommend settling these points up front.
Selling for Someone Outside Your Family
Platform rules vary. Autotrader says a private seller can only sell for someone else if they're a member of their family or household, shown by sharing an address or a family name.
Selling for anyone else counts as a trade sale on Autotrader. The platform says presenting a trade sale as a private one breaches its terms and UK law. Carwow takes a different view for occasional favours, saying you don't need to be in the motor trade to sell a car for a relative or friend.
Check each platform's rules before listing. If they don't fit your situation, consider selling to a trade buyer instead.
Advertising online: Autotrader allows two routes. The account can be set up in the owner's name with their permission, provided the owner is available for checks. Alternatively, list under your own name and state clearly in the advert that you're selling on someone else's behalf and aren't the owner.
If the Owner Has Lost Capacity
A letter isn't enough if the keeper can no longer make decisions for themselves. The seller must be acting under a registered Lasting Power of Attorney for property and financial affairs.
Signing the keeper's name on a V5C, contract or cheque without that authority can amount to forgery, even with good intentions.
If the Owner Has Died
Selling a car after a death follows a different process, with a postal DVLA route and questions about probate.
If the Car Is on Finance
A finance company owns a car on hire purchase or PCP until the agreement is paid. A seller needs the right to sell. The finance must therefore be settled first.
Ask the keeper to request a settlement figure from the lender.
Telling the DVLA
The registered keeper is responsible for telling the DVLA about the sale. GOV.UK's online service needs the 11-digit reference number from the V5C. The DVLA then cancels the vehicle tax and refunds any full months remaining.
If the keeper can't be at the handover, they may be able to complete the online notification themselves. Otherwise they need to complete the relevant V5C section.
When the buyer is a motor trader, GOV.UK says the trader can tell the DVLA online with the seller's consent.
If there's no V5C, the keeper must write to the DVLA with the sale details, including the registration number, the exact date of sale and the buyer's name and address. Vehicle tax isn't transferred. The buyer must tax the car before driving it.
If the Car Was Given to You
A relative may have given you the car while the V5C still shows them. Ask them to tell the DVLA they've put it in your name before you sell.
GOV.UK says to use the new keeper's name as the person the vehicle was sold to, even if no money changed hands.
Getting Paid Safely
Payment should go to the registered keeper or to the account they've named in writing. Never hand over the car until the money has cleared in that account.
Swansway Garages advises using a written sale agreement that records the price, date, registration, mileage and both parties' names and addresses. State that you're selling on the owner's behalf. The owner receives the full proceeds unless you've agreed otherwise in writing.
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Conclusion
Selling someone else's car is straightforward when the paperwork is right: the V5C, a signed letter of authority, ID for both people and the keeper's bank details. Extra care applies if the owner has lost capacity, has died or still owes finance.
Keep copies of everything and never sign for the keeper without authority.
Frequently Asked Questions
Can I sell a car that isn't in my name?
Yes, with the registered keeper's clear authority. A signed letter of authority is the minimum. Buyers commonly ask to see one.
Do I need power of attorney to sell someone's car?
Not if the owner can make their own decisions and agrees. A signed letter of authority is the minimum. A registered Lasting Power of Attorney is needed if they've lost capacity.
What documents do I need to sell a car for someone else?
The V5C, a signed letter of authority, ID for the keeper and the seller, proof of the address on the V5C and the keeper's bank details. A finance settlement letter is needed if finance is outstanding.
Who signs the V5C when selling for someone else?
The registered keeper should complete the relevant section or tell the DVLA online. Unless you hold a registered Lasting Power of Attorney, don't sign for them.
Who receives the money?
Payment normally goes to the registered keeper or to an account they've named in writing. Wait for the money to clear before handing over the car.
Can I sell a friend's car on Autotrader?
Autotrader says a private seller can only sell for a member of their family or household. Selling for anyone else counts as a trade sale on its platform.
Can I keep any of the money?
The owner normally receives the full proceeds. If you're to be paid for your time, agree it in writing first. Bear in mind that selling cars for payment can raise the trading question.
Can I sell someone's car if it's on finance?
Not until the finance is settled. The finance company owns the car until the agreement is paid. Ask the keeper to request a settlement figure first.