Once contracts are exchanged, both parties are legally committed to completing the transaction. If the seller refuses to complete — for any reason — they are in breach of contract, and you have legal rights.
What exchange means for the seller
At exchange, the seller:
- Signed a binding contract to sell the property to you on the agreed date for the agreed price
- Accepted your deposit (typically 10% of the purchase price)
- Committed to vacate the property and hand over keys on completion day
They cannot legally change their mind. They cannot validly sell to another buyer. They cannot raise the price. The contract is fixed.
What happens if the seller doesn't complete
If completion day arrives and the seller hasn't vacated, refuses to hand over keys, or otherwise refuses to complete, your solicitor will serve a Notice to Complete.
A Notice to Complete gives the seller a further 10 working days (by default, though the contract may specify a different period) to complete. During this period:
- Interest accrues on the outstanding purchase price at the contract rate — the seller owes this to you
- The seller remains in breach
If the seller still doesn't complete within the notice period:
You can rescind the contract: Your solicitor formally cancels the transaction. The seller must return your full deposit plus accrued interest. You also have the right to claim damages.
Or you can pursue completion through the courts: An order for specific performance forces the seller to complete. This is rare but available where the seller has the ability to complete but is refusing to.
What you can claim in damages
Beyond your deposit return, you can claim compensation for the losses caused by the seller's breach:
- Legal and professional costs: Solicitor's fees, survey cost, mortgage application fees
- Additional purchase costs: If you had to buy elsewhere at a higher price because the market moved, the price difference is claimable
- Bridging or storage costs: If you'd already committed to a removals van, storage, or temporary accommodation
- Mortgage arrangement fee: If your mortgage offer has now lapsed and a new one is needed
You must document and prove your losses. Keep all invoices and records.
Before exchange: no protection
It's worth emphasising: before exchange of contracts, a seller can pull out at any time, for any reason, without legal penalty. This is why gazumping (accepting a higher offer before exchange) is legal.
The only time you have the protections described in this Q&A is after exchange. This is why moving to exchange quickly is your best protection against the transaction falling apart.
Practical reality
Most sellers who get cold feet after exchange complete anyway when they receive a Notice to Complete and understand the legal consequences. The small number who truly refuse often settle quickly by returning the deposit with interest to avoid a costly legal fight. Full litigation to recover damages is relatively rare.
This Q&A is for general information. Dom does not provide legal advice. Consult your solicitor immediately if the seller fails to complete on the agreed date.