Selling a house at auction: how it works, what it costs and the risks

Selling a house at auction in England or Wales means the price is set by bidding on a fixed date. At a traditional auction, the sale becomes legally binding the moment the hammer falls, and completion usually follows four to six weeks later. In a conditional auction (often sold as the "modern method of auction"), the winning bidder usually pays a fee to reserve the house and then has a few weeks to exchange contracts.

Auctions can be quick and certain, but they aren't free and the price isn't predictable. This guide explains how each type works, what it costs, how long it takes, and when another route is likely to get you more money.

How does selling a house at auction work?

The main steps are the same whether the auction is held in a room, live-streamed or online only:

1. Choose an auctioneer. Ask whether your home suits auction, and what they'd recommend as the guide and reserve.
2. Agree the terms of appointment. These set out the auctioneer's commission, any other charges you'll pay and any charges the buyer will pay. RICS says you need to agree them before the auctioneer does anything.
3. Instruct a solicitor to prepare the legal pack. It sets out the special conditions of sale and can include title documents, searches, replies to standard enquiries and the Energy Performance Certificate (EPC). The auctioneer will also ask for ID for money laundering checks.
4. Agree the guide and reserve. You can usually fix the reserve nearer the day, once you've seen how much interest there is.
5. Marketing. The auctioneer lists the house, arranges viewings, and should keep you told about interest and any offers made before the auction.
6. Auction day. If the bidding reaches your reserve, the house sells to the highest bidder.
7. Completion. The buyer pays the balance and you hand over the keys on the date set in the contract.

As with any sale, you need an EPC before the house is marketed.

Traditional vs modern method of auction

There are two kinds of auction contract, and the difference matters a lot to a seller.

	Traditional (unconditional) auction	Conditional auction ("modern method")
When the buyer is committed	When the hammer falls: contracts are exchanged there and then	Only when contracts are exchanged after the auction
Money the buyer pays on the day	Normally a 10% deposit	Usually a non-refundable reservation fee (check the terms)
Time to exchange	On the day	Usually about four weeks after the auction
Time to complete	Usually four to six weeks after the auction	Set by the contract, after exchange
Suits buyers who	Have cash or finance ready	Need more time to arrange a mortgage

Traditional auctions give the most certainty. The usual rule that a contract to sell land must be a signed written document doesn't apply to contracts made at a public auction, which is why the sale is binding as soon as the hammer comes down. If the auctioneer uses the RICS Common Auction Conditions, completion is 20 business days after the auction unless you set a different timescale.

Conditional auctions give the winning bidder an option to exchange contracts at the hammer price within a set period, which RICS says is usually four weeks. You're committed to that bidder while the option runs, but they aren't legally bound until they exchange. So the sale can still fall through, and the extra time mainly helps buyers who need a mortgage.

Guide price and reserve price explained

• The reserve is the lowest price you'll accept. It's agreed between you and the auctioneer, and the house can't be sold below it. If the bidding doesn't reach it, the house doesn't sell.
• The guide is the figure published to bidders so they can decide whether to take an interest.

RICS says a guide should reflect the seller's minimum acceptable price. Its April 2025 practice alert reminds auctioneers that guides must reflect the expected reserve at the time they're published, and that a low guide set just to draw in bidders is misleading. If you raise your reserve after marketing starts, the guide should change too.

The practical point for you is simple: set the reserve at a price you'd genuinely be content to sell for, because that's exactly what you might get.

What does it cost to sell at auction?

Auctioneers set their own fees, so get them in writing before you sign anything. The costs usually look like this:

Cost	Who pays	What to check
Auctioneer's commission	Seller	Whether it's due if the house sells before or after the auction, or if you withdraw
Entry, listing or marketing fee	Seller	Whether you pay it even if the house doesn't sell
Legal pack and conveyancing	Seller	Your solicitor's quote, including searches
EPC	Seller	You may already have one, as they last 10 years
VAT	Seller	Fees from VAT-registered firms include VAT at the standard rate of 20%
Buyer's premium or admin charge	Buyer	It should be set out clearly in the particulars or conditions
Reservation fee (conditional auctions)	Buyer	Usually non-refundable if the buyer doesn't go ahead

Charges paid by the buyer aren't your bill, but they still affect you. A buyer works out what they can afford in total, so every pound of buyer fees is a pound less they can bid. RICS says that failing to set out all buyer fees clearly enough for bidders to work out the full cost up front is likely to be misleading.

How long does an auction sale take?

Auction sales are usually quicker than agent sales, mainly because the buyer has a fixed deadline. GOV.UK says selling a home takes about 5 months on average. With an auction, the timeline looks roughly like this:

1. Before the auction: your solicitor prepares the legal pack and the auctioneer markets the house. Ask the auctioneer how long their marketing period is and when they need the legal pack.
2. Auction day: at a traditional auction, contracts are exchanged and the buyer pays the deposit.
3. Completion: usually four to six weeks later at a traditional auction. For a conditional auction, add the option period of about four weeks before exchange, then the time to completion set in the contract.

If you need to sell by a particular date, a traditional auction gives you the clearest timetable.

What happens if the house doesn't sell at auction?

If the bidding doesn't reach the reserve, the auctioneer says the lot hasn't sold and doesn't bring down the hammer. RICS advises interested bidders to contact the auctioneer straight away, and the auctioneer will usually try to sell at or above your reserve after the auction, in line with your terms of appointment.

If it still doesn't sell, ask why. The usual reasons are a reserve that's too high for the condition of the house, a problem in the legal pack that put buyers off, or too little interest on the day. You can enter a later auction, try a different route or take the house off the market. Check whether any fees are still payable.

The risks of selling at auction

• The price isn't certain. You could sell at your reserve, with no competition above it.
• You're bound when the hammer falls. At a traditional auction there's no going back if you change your mind.
• Conditional buyers can still walk away before they exchange.
• Some fees may be due whatever happens, so read the terms of appointment closely.
• The legal pack must be accurate. The auctioneer will want to know about anything that might affect bids, such as disputes, notices or unpaid service charges. Missing or wrong information can delay or derail the sale.
• Buyers who need a mortgage have little time at a traditional auction, which narrows the field.
• A buyer may fail to complete. That's a breach of a binding contract, and your solicitor will advise on your rights under the conditions of sale.

When auction makes sense, and when it doesn't

Auction can suit you if:

• the house needs a lot of work, or is hard to mortgage, so it appeals mainly to cash buyers and investors
• it's unusual, so its value is hard to judge and competitive bidding helps find the price
• you're an executor or landlord who wants a fixed timetable and a binding sale
• you value certainty on the day more than getting every last pound

An estate agent is likely to get you more if:

• the house is in good condition and could be bought with an ordinary mortgage
• there's plenty of local demand for homes like yours
• you can wait a few months for the right buyer

In those cases, an open-market sale reaches far more buyers, including those who need a mortgage and the usual time to arrange it.

Auction vs a cash buyer vs an estate agent

	Estate agent	Traditional auction	Cash house buyer
Price	Usually the highest, at the open-market price	Set by the bidding, possibly at your reserve	Usually below market value
When it becomes binding	At exchange, often months later	When the hammer falls	At exchange
Main costs to you	Agent's commission and legal fees	Auctioneer's fees and the legal pack	Varies by buyer
Risk of collapse	Sales can fall through before exchange	Low once the hammer falls	Depends on the buyer

A cash buying company like ours is another quick option. We make an offer within 24 hours, pay your legal fees, charge no fees or commission and let you choose the completion date. Our offer is below market value, and we explain how we worked it out from recent sales nearby, so you can compare it with what an auction or an agent might achieve. For a fuller side-by-side look, see cash buyer vs estate agent vs auction.

Questions to ask an auctioneer

• Are you regulated by RICS, and which redress scheme do you belong to?
• Is this a traditional or a conditional auction?
• What will I pay, and when? What if the house doesn't sell, sells before the auction, or I withdraw?
• What will the buyer pay on top of the price?
• How will you set the guide and reserve, and what sold prices are they based on?
• How long is the marketing period, and how many homes like mine have you sold recently?
• What completion period do your conditions of sale use?

Auctions in Scotland work differently under Scottish law. This guide covers England and Wales only.