Gazumping and gazundering: what they are and how to protect yourself

Gazumping is when a seller accepts your offer, then accepts a higher one from someone else before contracts are exchanged. Gazundering is the reverse: a buyer cuts their offer late in the sale, often days before exchange, knowing the seller has a lot riding on it. Both are legal in England and Wales, because an offer isn't legally binding until contracts are exchanged.

You can't make either one impossible, but you can make it much less likely, and much less damaging if it happens. This guide explains how, for sellers and for buyers. It covers England and Wales; the rules are different in Scotland.

What is gazumping?

Say you agree to buy a house for £250,000. Your solicitor starts work, you pay for a survey and your mortgage is approved. Three weeks later the seller tells you someone else has offered £260,000 and they're going with it, unless you match it. That's gazumping.

It tends to happen when homes are selling quickly, when a home stays on the market after an offer is accepted, or when a sale is dragging and the seller gets nervous.

What is gazundering?

Now turn it round. You've accepted £250,000 for your home, found your next one and booked removals. The day before exchange, your buyer says they'll only pay £235,000. If you refuse, they'll walk away, and the chain you're in may collapse. That's gazundering.

It tends to happen when prices are falling or when the buyer thinks the seller can't afford to start again. It's different from a genuine renegotiation, where a survey or a lender's valuation turns up a real problem and the buyer can show you the evidence.

Why are gazumping and gazundering legal?

GOV.UK is clear: "An offer is not legally binding in England and Wales until contracts are exchanged." Until then, your home is "sold subject to contract", and either side can change the price or pull out. Even the memorandum of sale your estate agent sends round after you accept an offer is a summary of the deal, not a contract.

Two rules keep the door open until exchange:

• Estate agents must pass on every offer. GOV.UK says agents are "legally obliged to pass on any other offers for your home right up to when contracts are exchanged". The law requires them to forward offers promptly and in writing, unless you've told them in writing that you don't want offers of a certain kind.
• Nothing binds either side before exchange. Once contracts are exchanged, GOV.UK says neither of you can usually pull out without paying compensation. Before that, there's no contract to break.

Is the law changing?

The government's home buying and selling reform roadmap, updated in June 2026, says it will legislate to "require the use of binding conditional contracts in property transactions after sales packs are embedded". That would make deals binding much earlier, with set reasons for pulling out. It's planned for later in this Parliament and needs new law first, so as of October 2026 nothing has changed. For now the roadmap encourages the voluntary use of reservation agreements.

When the buyer is a quick-sale company

Gazundering isn't only something private buyers do. Some quick-sale buyers make an attractive offer to win the deal, then reduce it close to exchange, once the seller has taken the home off the market and planned the move. The reason given is often a survey or a "revised valuation".

The Property Ombudsman (TPO) has a code of practice for property buying companies. It says members:

• must give written confirmation of any offer or amended offer, with the proposed timescales
• must confirm any change to the offer in writing within 15 working days of the seller accepting it, unless an issue needs longer to investigate, in which case they must tell the seller in writing what it is
• should not cut the price late in the process without a valid reason, fully explained to the seller in writing
• must explain to sellers that they are free to use their own professional advisers

The code only binds members, so check whether a buyer belongs to The Property Ombudsman or the NAPB before you agree anything. Our guide on how to check a cash house buyer covers the other checks.

Cash house buyers, including us, usually pay below market value. A fair buyer tells you that at the start and explains how the offer was worked out, so there's less reason for it to move later. We make an offer within 24 hours, explain how we reached it from recent sales nearby, and there's no obligation to accept.

How sellers can protect themselves from gazundering

• Get the offer in writing, including the price, any conditions (survey, mortgage valuation, anything "subject to") and the timescale.
• Check the buyer can pay. Agents following TPO's code must take reasonable steps to find out where the buyer's money is coming from: whether they need to sell, need a mortgage or claim to be a cash buyer. Ask what evidence they've seen, such as a mortgage decision in principle or bank statements.
• Ask for proof of funds from a cash buyer. TPO's code says someone should only be called a cash buyer if the money will be available by exchange and completion, or they've already exchanged on their own sale and don't need a mortgage.
• Use an independent solicitor or conveyancer who acts only for you, and who can tell you whether a price cut is backed by evidence.
• Be ready to move fast. Have your documents ready and answer your solicitor's questions quickly. The shorter the gap to exchange, the fewer chances for a late cut.
• Know your walk-away price before you accept, so a last-minute demand doesn't push you into a decision you'll regret.
• Keep in touch with other interested buyers. Your agent has to pass on offers until exchange, so you may have a fallback.

If a buyer asks for a reduction, ask for the survey extract or valuation that justifies it. A genuine problem may be worth negotiating over. A demand with no evidence is a negotiating tactic, and you're entitled to say no.

How buyers can protect themselves from gazumping

If you're buying as well as selling, these steps reduce the risk of losing your next home:

• Ask the seller to take the home off the market. TPO's code says the agent must take the seller's instructions on this. If the seller keeps marketing it, the agent must tell you in writing and make clear an offer has been accepted.
• Ask for an exclusivity (lock-out) agreement, which gives you a set period to exchange while the seller agrees not to deal with anyone else.
• Consider a reservation agreement. GOV.UK's selling guide says these show commitment and may include a financial penalty for pulling out. Have your solicitor read it before you sign or pay anything.
• Have your mortgage and deposit ready. A decision in principle and an early survey show you're serious.
• Watch for a contract race. In a contract race, the seller sends contracts to more than one buyer and sells to whoever is ready to exchange first. TPO's code says that if the agent knows the seller has told their solicitor to send a contract to another buyer, the agent must tell you in writing.

Can an agent invent a rival offer?

No. TPO's code says that by law an agent must not misrepresent or invent the existence or details of any other offer. If you think an agent has misled you, complain to the agent first. GOV.UK says that if you're still unhappy, you can go to The Property Ombudsman or the Property Redress Scheme, depending on which one the agent belongs to.

If it happens to you

Before exchange you usually can't recover money you've spent on surveys, mortgage fees or legal work, unless you signed an agreement that says so. Your realistic choices are to negotiate, walk away, or start again with another buyer or home.

If a sale collapses, our guide to what happens if a house sale falls through explains the next steps. If you need certainty more than the highest price, comparing your options in below market value explained can help you judge whether a lower, firmer offer is worth it. When your home is in good condition and you can wait, an estate agent sale will usually get you more.