Is an offer on a house legally binding?
Short answer: yes. Making an offer feels to many buyers like an opening move in a negotiation — something you can still walk away from. Legally, that is not the case. Once the seller accepts your offer fully and unconditionally, the sale is concluded. Not at the compromis, not at the notary: at that moment. This guide explains what that means, where the pitfalls are, and how to write an offer that protects you.
Why an offer is binding
Under Belgian law, a sale is formed as soon as buyer and seller agree on the property and the price. An offer that precisely and unconditionally describes the property and the amount is therefore a genuine legal proposal. If the seller accepts it, an agreement exists — even though no compromis has been signed yet and you have not been to the notary. The compromis later sets out the details in writing; the deed formalises the transfer of ownership afterwards. But the obligation arises the moment the offer is accepted.
If you then want to back out without a valid reason, you risk having to pay damages — in practice often calculated as a percentage of the price — or even being forced to complete the purchase. Think twice before you put an amount on paper, not after.
Does this also apply to a verbal offer, a text message or an email?
In principle, a verbal offer can also be binding: the principle of mutual consent makes no distinction between spoken and written agreements. In practice, a verbal offer comes down to evidence — your word against the seller's. A text message usually does not count as full proof, but it can serve as a starting point of proof together with other elements such as earlier emails.
The practical conclusion is twofold. Always make a serious offer in writing, so the conditions are fixed. And be careful with what you communicate informally: "I'd be willing to pay €X" in a message can carry more weight than you intended.
The pitfall almost no one knows: an offer without an end date
If you do not state a validity period, your offer remains open until the property is sold. That means a seller can in principle accept your offer weeks or even months later — at a point when you may already have your eye on another home. You would then be obliged to complete the purchase.
Always include a clear deadline in every offer, for example: "This offer is valid up to and including [date]." After that date it automatically lapses and you are free again.
When does your offer lapse?
- The deadline expires. If you included a validity period and the seller does not respond in time, you are no longer bound.
- The seller refuses. A refused offer does not revive on its own; if you want to bid again, that is a new proposal.
- The seller makes a counter-offer. Important: a counter-offer cancels your original offer. The seller can no longer fall back on your first amount afterwards — and neither can you.
- The seller accepts with reservations. Only a full and unconditional acceptance creates the sale. "Agreed, but…" is legally a counter-offer.
How to protect yourself: conditions in your offer
Binding does not mean unconditional. You may — and in most cases should — include conditions in your offer. The most important ones:
- Condition precedent for financing. The sale only proceeds if you obtain a mortgage loan on reasonable terms within a set period. Without this clause you are locked into the purchase even if the bank refuses.
- A validity period for the offer. See above — always include one.
- Optionally: a technical survey or the sale of your current home. Depending on your situation. Draft conditions concretely and realistically; vague clauses lead to disputes.
A well-drafted offer states at least: the address of the property, the amount offered, the conditions, the validity period and your signature. If you are unsure about the wording, have your notary review it — it costs nothing extra and prevents costly misunderstandings.
Frequently asked questions
Can I withdraw my offer before the seller responds?
As long as the seller has not yet accepted your offer and you did not promise a period during which you would honour it, withdrawal is in practice sometimes possible — but it is legally delicate ground. Do not rely on it as an escape route; instead set a short validity period and only offer what you are truly willing to pay.
The seller verbally said "yes". Is the sale then concluded?
A verbal acceptance can be enough to create the sale, but it is hard to prove. Always ask for written confirmation (an email is enough) and have the compromis drawn up quickly afterwards.
I offered without a financing condition and my loan was refused. What now?
You are then in principle bound to the sale and risk having to pay damages if you cannot complete it. Contact your notary as soon as possible to review your options. This is exactly the scenario a condition precedent for financing is meant to prevent.
Is bidding above the asking price extra risky?
The binding nature is the same, but the financial consequences are bigger: you pay more than the listed price and the bank may accept a lower value as collateral. Read our guide Overbid or underbid?
An offer is not a trial balloon but a commitment. Buyers who understand that bid more carefully: in writing, with conditions, with a deadline, and within a budget set in advance. Read more on setting that amount in How much to bid on a house in Flanders.
Sources: notaris.be – How do I make a safe offer? · notaris.be – The private sale
Read more
How much to bid on a house in Flanders
Practical buyer guide: asking price vs offer, common mistakes, and a step-by-step approach to bidding realistically in Flanders.
Read the guideCalculate property value in Flanders
Market value, appraisal value and bank value explained. What drives price and when do you need an expert?
Read the guideOverbid or underbid?
When bidding above asking price makes sense — and when it doesn't. Risks and a simple decision framework for buyers.
Read the guideBuying your first home: setting your offer
Timeline from search to offer, where data helps, and a checklist for first-time buyers in Flanders.
Read the guideIs an offer on a house legally binding?
An offer on a home becomes legally binding once the seller accepts it. What that means, and how conditions and a validity period protect you.
Read the guideRegistration duties in Flanders (2026): what do you pay on top of your offer?
2% or 12% registration duties in Flanders? The rates and the stricter conditions since 2026, with worked examples for buyers.
Read the guideFrequently asked questions
Answers about het juiste bod: not an estate agent, market data, coverage, pricing, privacy and how we differ from listing sites.
Read the guideLast updated: July 2026.