
Before contracts can be exchanged, a few boxes need to be ticked as follows:
The exchange of contracts is one of the two key moments of your purchase process. This is the moment when the deal becomes legally binding on both sides and neither side can withdraw without significant consequences.

The actual “exchange” of the contracts in reality is a phone call between the solicitors acting for the seller and the buyer during which they read out the signed contracts by their respective clients to make sure they hold identical copies, insert the completion date, the available deposit, any agreed sums for additional items such as furniture or allowances and reductions in relation to any indemnity policies. Finally, they date and time the contract which makes it effective from that moment precisely.
From this moment, the risk for the property passes onto the buyer (unless it is a new build property, in which case the risk passes from completion) and that is why they need to place on risk a buildings insurance policy from this date.
Exchanging the contracts is legally binding. This means that if the buyer no longer wishes to proceed with the purchase after contracts have been exchanged, then they will lose their deposit and may also need to pay interest and compensation to the seller. The same goes for the seller, if they decide not to complete the sale, they would have to return the deposit to the buyer and may also need to pay any costs, compensation and/or interest to the buyer.
In certain unusual circumstances, exchanging the contracts and completion can happen on the same day.

It is important to remember that before contracts are exchanged, the deal is not 100% certainly going ahead so it is not reasonable to give notice to your current landlord (if you live in a rented accommodation) or your current employer (if you are changing jobs) yet. Even if you have informally agreed a completion date with the seller in advance, this date is not certain until after contracts are exchanged. Only then can you tell your removal company, landlord and employer when your move-in day would be.
You can use Appendix 12 of Part One of the book “How to buy your first home in England (and Wales)” to find ideas and create your own to-do list with tasks to complete at this stage of the process.