Exchange of Contracts and Completion Day Explained

After months of solicitors, searches, surveys and waiting, the property buying process comes down to two defining moments: exchange of contracts and completion. They're often talked about together but they're distinct events — one makes the transaction legally binding, the other physically transfers ownership.

Understanding what happens at each stage, and what you need to do before each one, means you're not caught off guard when your solicitor says you're ready to exchange — or left scrambling on completion day because something wasn't in place.

Exchange of Contracts: The Point of No Return

Exchange of contracts is the moment the property transaction becomes legally binding for both buyer and seller. Before exchange, either party can walk away without legal penalty. After exchange, neither side can withdraw without serious financial consequences.

In practice, exchange happens through a phone call between the buyer's solicitor and the seller's solicitor. Both solicitors confirm that their clients have signed identical contracts, that the deposit has been transferred, and that a completion date has been agreed. The exchange is then confirmed simultaneously — both solicitors legally bound at the same moment.

The deposit — typically 10% of the purchase price — transfers to the seller's solicitor at exchange, not at completion. This deposit is held until completion day. If the buyer pulls out after exchange without legal justification, they forfeit the deposit. If the seller pulls out, they face legal action for costs and damages.

A completion date is written into the contract before exchange can take place. This date is then legally binding for both parties — it cannot be changed unilaterally once contracts have been exchanged.

What Has to Be in Place Before Exchange

Exchange cannot happen until a series of conditions have been satisfied. Your solicitor will not exchange until all of the following are complete:

All searches returned and reviewed. Local authority, environmental, and water and drainage searches must be back, reviewed, and any issues resolved or accepted. Our guide to what is conveyancing covers what each search covers and typical timescales.

All enquiries answered. Any questions your solicitor has raised with the seller's solicitor — about planning permissions, building regulations, boundaries, lease terms, or anything else — must have been answered to your solicitor's satisfaction.

Survey completed and any renegotiation resolved. If the survey identified issues that led to a price renegotiation, that negotiation needs to be concluded before exchange. Our guide on what happens after an offer is accepted explains how surveys and renegotiations fit into the overall timeline.

Formal mortgage offer issued. Your lender must have issued a written mortgage offer — not just an agreement in principle. This confirms the loan is approved and the funds will be available at completion.

Buildings insurance arranged. This is the detail that catches most buyers off guard — you must have buildings insurance in place from the moment of exchange, not completion. As soon as you exchange, you are legally responsible for the property even though you don't own it yet.

Deposit funds transferred to your solicitor. Your solicitor needs the 10% deposit in their account before they can exchange. Transfer this well in advance — don't leave it to the morning of exchange day.

How Exchange Day Works in a Chain

In a simple transaction with no chain, exchange is straightforward. In a chain — where multiple buyers and sellers are linked — exchange is a coordinated process that all happens simultaneously, and it is more complex.

Most exchanges happen between 10am and midday, though in a long chain the process can run into the afternoon. If the release time passes without the chain completing, the whole exchange must be rescheduled for another day — which is why your solicitor will set a buffer in the release time.

Between Exchange and Completion

The period between exchange and completion — typically one to four weeks, though it can be anything both parties agree to — is when you can finally commit to practical arrangements with confidence, because the deal is now legally binding.

Book your removal company. If you haven't already, this is when you should lock in a removal firm. Popular completion dates — particularly Fridays — get booked up quickly. Try to avoid the Friday of a long weekend if you can, as any delays can push handover into the weekend when banks and solicitors aren't operating.

Notify utilities, broadband, and the electoral roll. Contact your energy provider, water company, broadband provider, and local council to arrange transfers to your new address.

Arrange a final inspection. Most buyers are entitled to a final pre-completion inspection of the property, usually in the days immediately before completion. Use this to confirm the property is in the condition agreed at exchange, that the seller has removed their belongings, and that anything included in the sale is still present.

Transfer completion funds to your solicitor. Your solicitor will confirm the exact amount needed — this is the total purchase price minus your deposit, plus any fees and stamp duty. Transfer this the working day before completion. Do not leave it to completion day itself — bank transfer delays on the day can push back key release by hours.

Completion Day: What Actually Happens

Completion is the day the property legally changes hands. On this day:

Your solicitor sends the completion funds — your deposit plus your mortgage advance — to the seller's solicitor. In a chain, money passes up through each transaction simultaneously.

The seller's solicitor confirms receipt of funds and notifies the estate agent to release the keys.

The estate agent calls you to confirm the keys are available for collection. This typically happens between late morning and early afternoon, though in a long chain it can run later.

You collect the keys. The property is yours.

Your solicitor registers the title in your name at HM Land Registry and pays stamp duty to HMRC within 14 days of completion. You will receive the title deeds — usually electronically — once registration is confirmed, which can take several weeks.

The seller must vacate the property and hand over all keys before a specified time — usually midday or early afternoon. If the seller has not vacated by the agreed time and this causes you to incur costs, such as removal company delays or overnight accommodation, you may be able to recover those costs from the seller.

What Could Go Wrong on Completion Day

Completion problems are rare but they do happen. The most common issues are:

Funds not arriving in time. Bank transfers of large sums take time to clear, and delays at any link in the chain can push back key release for hours. Mortgage lenders sometimes release funds late. This is why sending your completion funds the day before is strongly recommended.

The seller hasn't vacated. Occasionally sellers are still in the property or removing furniture when the completion confirmation comes through. If this happens, your solicitor and the estate agent will manage the situation — but it can delay when you can physically move in.

Last-minute mortgage issues. In rare cases, lenders apply unexpected conditions before releasing funds, or a problem emerges with the mortgage offer on completion day. Having your solicitor in regular contact with your lender in the week before completion reduces this risk.

Before any of this, the most important thing you can do is ensure the price you're paying reflects what the property is actually worth. Brix&Mortr gives you an independent check on value using real HM Land Registry sold prices for comparable properties — so you approach exchange confident in your position.

Frequently Asked Questions

What is the difference between exchange and completion?

Exchange is when contracts are signed and the transaction becomes legally binding. Completion is when ownership transfers and you get the keys. Exchange typically happens one to four weeks before completion, with a completion date agreed at the point of exchange.

Can I pull out after exchange?

Technically yes, but at serious financial cost. If you pull out after exchange as a buyer, you forfeit your deposit — typically 10% of the purchase price. If the seller pulls out after exchange, they can be sued for costs and damages. Pulling out after exchange is extremely rare.

What time do you get the keys on completion day?

Usually between late morning and early afternoon — often around midday, though this depends on how quickly funds clear through the chain. In a long chain, key release can run into the afternoon. Your estate agent will call you once the funds have been confirmed.

How long between exchange and completion?

Typically one to four weeks, though it can be anything both parties agree to. Same-day exchange and completion is possible in simple, chain-free transactions but is not recommended as it leaves no room for logistical problems.

Do I need to be present at exchange or completion?

No — your solicitor handles both exchange and completion on your behalf. You don't need to visit their office. On completion day, you simply collect the keys from the estate agent once your solicitor confirms funds have cleared.