Mortgage affordability calculator
To work out how much you can afford, use our mortgage affordability calculator.
Last updated:
03 March 2025
Buying a home can be incredibly stressful. You’ve likely saved up for years, had tough conversations, viewed a lot of places - there’s a lot on the line.
When you eventually get a mortgage offer, it can feel like you’re on track to getting your dream home. But what can go wrong after it?
There’s always a chance that the seller of the home you’re buying might pull out of the sale. There are a few reasons why that could happen.
When you buy a property, you’re often relying on the person who’s selling it to find somewhere to move to. If they are buying another home, this is known as a “chain”.
A property chain is a series of linked house purchases that all need to take place to complete the chain. If there are a lot of people in your chain, that means there’s more room for things to go wrong.
If there’s something wrong with the property your seller is trying to buy, they might break the chain and your sale can fall through.
Some examples could be that the survey on the house they’re buying has come back with a load of expensive problems, and they don’t want to take on the responsibility, so decide to buy somewhere else.
Or, maybe the seller has found something better for them or their mortgage offer expired before you could all get it across the line.
If you’re in a chain, you might find that your buyer could pull out too for the same reason. There’s not a lot you can do at this stage but just wait with your fingers crossed so that it all works out.
Buying a property can take a very long time; typically, three to six months – but it could go on even longer if there’s a long chain or if the purchase is complicated.
In that time, a lot can happen financially. You could lose your job or maybe you might get a promotion and decide you want a more expensive house. If you’re purchasing with other people, there’s the possibility they will decide to pull out and you can no longer afford the property.
Sometimes buyers find that after the survey has been completed, they discover there’s a lot of work that needs to be done and it’s no longer affordable.
Lenders will perform a credit check when you apply for a mortgage, and if you have a poor credit score, your application might be turned down.
To help avoid this, you can check your credit file with a credit reference agency, such as:
Once you understand your credit score, you’ll want to look at improving your credit rating. View our guide on How to improve your credit score.
Working with a solicitor or conveyancer, can be one of the more frustrating things about buying a home, as they can take a long time to do the work and will cost you a lot of money. However, they are a vital part of the process, as they are there to help you through any legal issues that might come up.
For example, you may find that as things are about to go through, you spot a mistake in the contract which you need to get sorted, which then means the offer is withdrawn. It’s always a good decision to not fully rely on your solicitor, and to double check everything you’re being asked to sign.
If you’re buying or selling a leasehold property, that opens you up to potential legal complications too. For example, you may find out when you’re already going through the process that your buyer wants you to extend the leasehold, which is expensive and complicated.
The length of your mortgage offer can vary, typically from six months to a year (so make sure you check and put the end date in your diary), but because so much can go wrong, they can expire if you’re unlucky. It sounds like a long time, but typically, people only start looking for a property once they know how much money they have to spend, and then you need to add the three to six month process of buying on top of that. It’s easy to see how it could potentially hit that year point.
However, make sure you keep updating your mortgage provider, who would potentially extend your offer, or quickly make a new one to avoid the purchase falling through. Although they may re-do a credit check and ask for new evidence.
Join our private Budgeting and Saving Facebook groupOpens in a new window for money-saving tips and support from a community of savers.