Gazumping and gazundering explained

If you’re buying or selling property in England or Wales, you may have heard the terms gazumping and gazundering.

Gazumping is when a seller accepts your offer and then later accepts a higher offer from someone else before contracts are exchanged.

Gazundering is when a buyer agrees a price and then lowers their offer shortly before exchange of contracts.

In both cases, the reason it can happen is the same: in England and Wales, an accepted offer is not legally binding. Only exchange of contracts makes the deal legally secure. Until that point, either side can change their position.

That’s the legal reality. Everything else follows from that.

The gap between agreement and certainty

When an offer is accepted, most people mentally move in. Buyers start planning furniture. Sellers begin searching seriously for their next home. The deal feels done. But legally, it isn’t.

The conveyancing process can take weeks or months. During that time:

• Surveys are carried out.
• Mortgage approvals are confirmed.
• Legal enquiries go back and forth.
• Chains have to align.

All of this happens before contracts are exchanged.

That long non-binding phase creates uncertainty. And uncertainty creates opportunity for positions to change.

If another buyer appears with a stronger offer, a seller may decide to switch. If a survey uncovers problems or a lender down-values the property, a buyer may renegotiate.

The system allows it, even if it feels unfair.

Gazumping in practice

Gazumping is more common in stronger or rising markets. Demand is high. Properties attract multiple offers. Sellers feel confident they can achieve more.

From a seller’s perspective, accepting a higher offer may seem commercially rational, particularly if the new buyer is chain-free or able to move faster.

From a buyer’s perspective, it can feel like the rug has been pulled out from under you, especially after paying for searches, surveys and mortgage fees.

But until exchange, the seller has no legal obligation to proceed with the original agreement.

Gazundering in practice

Gazundering tends to appear in slower or uncertain markets.

Buyers may feel prices are softening. They may believe the seller is under pressure. They may reassess risk late in the process.

Sometimes a reduced offer is grounded in new information, structural issues, leasehold complications, or a lender’s down-valuation. In those situations, renegotiation can be reasonable.

Other times, it is tactical. The buyer waits until just before exchange, knowing the seller is financially and emotionally committed.

Again, it is only possible because the contract has not yet been exchanged.

Why the system works this way

In England and Wales, we agree a price before completing due diligence. The detailed checks come later.

That sequencing creates a long window where neither side is legally bound.

In Scotland, by contrast, the legal commitment happens much earlier in the process. That structural difference is why gazumping and gazundering are far less common there.

This is not about culture. It is about timing and legal framework.

What you can realistically do

You cannot eliminate the risk entirely. But you can reduce it.

If you are buying, preparation and pace matter. Having your mortgage decision in principle ready, instructing your solicitor quickly and returning documents promptly all signal commitment. Sellers are less likely to entertain higher offers if progress is steady and visible.

If you are selling, the strength of the buyer matters more than the highest headline price. A chain-free buyer with finance in place is usually lower risk than a slightly higher offer built on uncertainty. Responding quickly to enquiries and keeping momentum reduces the opportunity for last-minute renegotiation.

Most importantly, distinguish between genuine new information and shifting leverage. Not every price change is bad faith. The key question is whether something material has changed.

Be prepared, not surprised

Gazumping and gazundering are possible because agreement comes before legal certainty.

You can’t remove that risk entirely. But you can reduce it by moving quickly, understanding the property properly, and keeping experienced professionals around you.

A good surveyor helps you assess risk early. A responsive conveyancer keeps momentum. A mortgage adviser makes sure your finance is solid before exchange.

If you want to approach the process with more clarity and fewer surprises, start by building the right team around you.

Find a surveyor, conveyancer or mortgage adviser near you below.