What is a memorandum of sale in property auctions?
A memorandum of sale is one of the most important documents in any auction property purchase — yet many buyers are unfamiliar with it until the moment they are asked to sign. Understanding what a memorandum of sale is, what it contains, and why it carries legal weight is essential if you are planning to bid at auction.
Unlike a standard open market sale, where contracts are exchanged days or weeks after an offer is accepted, an auction property purchase works very differently. The moment the hammer falls, a legally binding contract is formed. The memorandum of sale is the written record of that contract — and signing it is not a formality.
This guide explains everything you need to know about the memorandum of sale in the context of a UK property auction, including what it contains, how it relates to the wider contract, and what mistakes to avoid when signing.
What is a memorandum of sale?
A memorandum of sale is a document issued by the auctioneer immediately after a property lot is sold. It records the fundamental terms of the sale agreed on auction day, including the identity of the buyer and seller, the purchase price, and the key conditions that apply to the transaction.
In a standard residential sale, a memorandum of sale is used in a non-binding, administrative sense — it simply records that an offer has been accepted and instructs solicitors to begin the conveyancing process. At this stage, nothing is legally binding.
In an auction context, the memorandum of sale works quite differently. Because the contract is exchanged at the fall of the hammer, the memorandum of sale forms part of the legally binding agreement from the outset. Signing it confirms that you have entered into a binding contract — and there is no cooling-off period, no room for renegotiation, and no withdrawal without serious financial consequences.
Is a memorandum of sale the same as the contract?
No — but in an auction property purchase, it forms a critical part of it. This is a distinction worth understanding clearly.
In a conventional sale, the contract is a separate document that is negotiated, reviewed, and exchanged at a later date. Solicitors on both sides go through a detailed process before anything becomes legally binding.
At auction, that process is compressed into a single moment — the fall of the hammer. The full contract in an auction transaction is typically made up of three components working together:
- The memorandum of sale — records who bought, who sold, at what price, and on what date
- The Special Conditions of Sale — additional terms specific to the lot, which can override the standard conditions
- The Common Auction Conditions — the standardised framework that governs how auction sales work across the industry
Together, these three documents form the legally binding contract for your auction property purchase. The memorandum of sale is the starting point — the document that ties everything together from auction day onward.
Understanding the Special Conditions of Sale is particularly important, as they can impose significant obligations on the buyer that go beyond the standard terms. The special conditions of sale guide explains what these clauses commonly contain and the risks they can introduce.
What happens if you pull out after winning a property auction?
Pulling out after the hammer falls puts you in auction breach of contract. The seller is entitled to enforce the contract, and the consequences are not limited to simply losing your deposit. In a worst-case scenario, they can pursue you for every financial loss your withdrawal causes them.
Here is what you can expect to face:
- Loss of your 10% deposit. At a traditional auction, you pay a deposit — typically 10% of the purchase price — immediately on the day. If you withdraw, this is forfeited in full. On a £300,000 property, that is £30,000 gone.
- Liability for the seller’s costs. The seller can recover their legal fees, auctioneer’s commission, and other costs incurred as a result of the failed sale directly from you.
- Damages for market depreciation. If the seller has to re-sell the property and achieves a lower price than the original auction sale, they may be able to pursue you for the difference. If property values have fallen in the intervening period, this liability can be substantial.
- Carrying costs. The seller may also claim ongoing costs incurred while the property remains unsold — mortgage interest, insurance, maintenance, and storage in some commercial cases.
- Specific performance. In rare circumstances, a court can order you to complete the purchase rather than simply pay damages. This is an unusual remedy but it exists.
The combined financial exposure from an auction breach of contract can far exceed the 10% deposit. This is why it is not simply a matter of deciding to walk away and accepting that you will lose your deposit money. You may owe considerably more than that.
What does a memorandum of sale include?
The memorandum of sale is typically a concise document, but every detail it contains is legally significant. A standard memorandum of sale for an auction property purchase will include the following:
- The full address of the property sold
- The full legal names of both the buyer and the seller
- The names and contact details of both parties’ solicitors
- The final auction sale price achieved
- Confirmation of the deposit paid — typically 10% of the purchase price
- The agreed completion date — commonly 14 or 28 days from auction day for unconditional sales
- Reference to any special conditions or additional fees noted in the auction legal pack
Although the document may appear straightforward, each entry carries real legal consequence. The buyer’s name recorded on the memorandum of sale is the name that will be registered as the legal owner of the property. If the wrong name is entered — for example, a personal name when the purchase is being made through a company — correcting it later can be complex, time-consuming, and costly.
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Why the memorandum of sale matters for your solicitor
Once the memorandum of sale is signed, it is sent to both parties’ solicitors as confirmation that a legally binding auction property purchase has taken place. From this point, the clock is ticking. Completion must happen within the timeframe specified — typically 28 days for a traditional unconditional auction.
Your auction conveyancing solicitor will use the memorandum of sale to:
- Confirm the terms of the transaction and begin post-auction legal work immediately
- Liaise with the seller’s solicitor to prepare and review the transfer documentation
- Request any outstanding information from the auction legal pack
- Raise any final enquiries that need resolving before completion
- Coordinate with your mortgage lender or bridging finance provider if applicable
This is why it is so important to have an auction conveyancing solicitor instructed before auction day, not after. When the memorandum of sale arrives, work should begin immediately. You can learn more about what happens after the hammer falls and the steps your solicitor takes to progress the transaction towards completion.
What to check before you sign the memorandum of sale
In the adrenaline of winning a lot at auction, it can be tempting to sign quickly and move on. But the memorandum of sale should always be reviewed carefully before you put pen to paper. Here are the most important things to verify:
Your name and legal entity
Make absolutely certain that the buyer’s name reflects exactly how you intend to hold the property. If you are purchasing as an individual, your full legal name must appear. If you are buying through a limited company or a trust, the correct legal entity must be recorded. This cannot easily be changed after signing without potentially triggering additional costs or tax implications.
The purchase price
Confirm that the price recorded matches the final hammer price. In most cases this will be straightforward, but it is worth double-checking before you sign — particularly if there was rapid bidding near the close of the lot.
The completion date
The memorandum of sale will state the completion date or the number of days from auction within which completion must occur. Ensure your funding arrangements can meet this deadline comfortably. Missing a completion deadline in an auction transaction can result in daily interest charges and, in serious cases, forfeiture of your deposit.
Special conditions and additional fees
Some lots carry buyer’s fees — such as administration charges payable to the auctioneer — or special conditions that impose costs or obligations beyond the purchase price. These should have been identified during your review of the auction legal pack before bidding. If anything in the memorandum is unclear, speak to your solicitor before signing.
What happens if you refuse to sign the memorandum of sale?
Refusing to sign the memorandum of sale after winning at auction is not a viable option. The contract is formed at the fall of the hammer, not at the point of signing. The memorandum of sale is simply the written confirmation of that pre-existing legal obligation.
If you fail to sign, fail to pay the deposit, or withdraw from the transaction after the hammer has fallen, you will be in breach of contract. The consequences can be severe:
- You will lose your deposit in full
- The seller may pursue you for any shortfall if the property subsequently sells for less
- Legal costs and interest charges may be added to the claim
- Your credit record and professional reputation may be affected if the matter proceeds to litigation
This underlines why thorough preparation before bidding is so important. The time to identify problems, raise concerns, and seek legal advice is before auction day — not after the hammer has fallen.
The auction legal pack contains all the information you need to make that assessment. A specialist review of the pack can identify risks, flag missing documents, and give you a clear picture of what you are committing to. See what we check in an auction legal pack for a full breakdown of our review process.
How does a memorandum of sale work in a conditional auction?
The rise of online and conditional auction formats has introduced a variation on the traditional process. In a conditional auction, the fall of the hammer — or the close of an online bidding period — does not immediately form a binding contract. Instead, a reservation agreement is signed, and the buyer has a fixed period (typically 28 to 56 days) to exchange contracts and complete.
In this format, the memorandum of sale is still issued, but it records the terms of the reservation agreement rather than an immediate exchange. The buyer pays a non-refundable reservation fee rather than a 10% deposit. If the buyer fails to proceed, they lose the reservation fee but are not exposed to the same level of liability as in an unconditional auction.
This distinction is important because it affects the legal risk profile of the transaction from day one. Whether you are buying through an unconditional or conditional auction format, understanding exactly which type you are entering is essential before you bid.
For a clear explanation of how conditional and unconditional auctions differ — and the legal implications of each — the NAEA Propertymark guidance on buying at auction provides a helpful independent reference point.
Summary: what you need to know about the memorandum of sale
A memorandum of sale is the document that records and confirms the terms of your auction property purchase immediately after the hammer falls. It is not simply an administrative form — it is a legally significant part of the binding contract entered into on auction day.
Before you sign, check every detail: your name, the purchase price, the completion date, and any special conditions or fees. Errors at this stage are far harder to correct than errors identified before bidding begins. Once the memorandum is signed and the deposit paid, you are committed.
At AuctionSolicitor, we work with buyers from the moment they identify a lot through to post-auction completion. We review the auction legal pack in advance, advise on any risks identified, and begin post-auction conveyancing immediately once the memorandum of sale is received — so you never lose a day of your completion window.
If you are preparing to bid, upload your auction legal pack for a pre-auction review and we will give you a clear legal report before you step into the auction room.
Ready to bid? Get your auction legal pack reviewed first.
The memorandum of sale is signed at the fall of the hammer — and every term in it is immediately binding. Our specialist solicitors review your auction legal pack before you bid, flag any risks in the special conditions, and begin your post-auction conveyancing the moment your memorandum arrives.
