What is gazumping and how can I avoid it?

Being gazumped is one of the most deflating moments in buying a home. You have had your offer accepted, told your family, maybe paid for a survey, and then the call comes that the seller has taken a higher offer from someone else. It feels unfair, and it is worth understanding why it is allowed and what genuinely reduces the risk.

What does gazumping actually mean?

Gazumping is when a seller who has verbally agreed to sell to you accepts a better offer from another buyer before contracts are exchanged. Until exchange, an agreed sale in England and Wales is a promise, not a contract, so the seller is free to change their mind. Gazumping is not the same as gazundering, which is when a buyer lowers their offer at the last minute.

Is gazumping legal in the UK?

In England and Wales gazumping is legal, because a property sale only becomes legally binding when contracts are exchanged (gov.uk, Buying and selling a home). Everything before exchange, including the accepted offer and the sold subject to contract stage, can be walked away from by either side without penalty. Scotland works differently: offers there are made through formal letters called missives and become binding much earlier, so gazumping is far rarer north of the border.

How likely am I to be gazumped right now?

Outright gazumping is only one way a deal can collapse, and the wider fall-through numbers show why the early weeks matter. In the first quarter of 2026, 23.7% of agreed UK sales fell through, down slightly from 24% (PropertyWire, May 2026). The risk is front-loaded, so the faster you move, the safer you are.

How do I avoid being gazumped?

You cannot make an agreed sale legally binding before exchange, but you can close the gap where gazumping happens. The aim is to be the buyer who is ready, quick, and easy to deal with, so the seller has no reason to look elsewhere.

1. Get a mortgage agreed in principle before you offer, so the seller can see you are ready to proceed.
2. Instruct your solicitor the same day your offer is accepted, rather than waiting a week or two.
3. Book your survey early instead of leaving it until searches are back.
4. Ask the agent to mark the listing as sold subject to contract and, if the seller agrees, to stop new viewings.
5. Reply to every request from your solicitor and the agent quickly, because delays are what let another buyer catch up.
6. For a property you really want, ask about a lock-out agreement, and consider home buyer protection insurance to cover wasted costs.
7. Stay friendly with the seller where you can, since a seller who feels a connection is less likely to drop you for a small extra sum.

What is a lock-out agreement and does it work?

A lock-out agreement, also called an exclusivity agreement, is a short contract in which the seller agrees not to negotiate with any other buyer for a fixed period, usually 28 to 56 days. Unlike the sale itself, it is binding from the moment it is signed. You normally pay a fee for it, and if the seller breaks it you can claim your wasted costs back, though it still does not force them to sell you the home. It buys time and commitment, not certainty.

Common questions about gazumping

The calm way to think about it

Gazumping feels personal, but it is really a timing problem. The longer a sale sits between agreement and exchange, the more chance something, or someone, disturbs it. Being organised is not glamorous, yet it is what keeps a sale yours. The decision to sell, and to whom, always belongs to the seller until exchange, which is exactly why moving quickly is the buyer's strongest card.

ValuQ gives UK homeowners free, side-by-side property valuations from competing local estate agents, so a seller can choose the right agent on merit before a home ever goes on the market and the process begins on a steady footing.