Getting a mortgage in principle

Mortgage in principle, decision in principle and agreement in principle: there are lots of terms for the same thing, but what does it really mean? Below, we’ve put together a comprehensive guide on getting a mortgage in principle.


From what it is to how long it takes to get a mortgage in principle and how to apply – find all you need to know here.

What is a mortgage in principle?

A mortgage in principle, or agreement in principle (AIP), is a statement from your lender of how much they’re prepared to lend you ‘in principle,’ based on basic information such as your salary, how much you’d like to borrow and your monthly outgoings.

However, as the offer is in principle, it’s not set in stone. Should you make a formal application with the same lender at a later date, the lender reserves the right to change the details of the loan or to decide not to go forward with the loan all together. The reason for this change will be made clear in your application process.

Getting a mortgage in principle can make you a more attractive buyer, as it shows the seller and estate agent that you’re serious about the purchase.

Does a mortgage in principle guarantee a mortgage?

No, a mortgage in principle does not guarantee a mortgage. This is because the lender only has a limited view of your financial situation. For this reason, getting an agreement doesn’t guarantee a mortgage nor does it make any guarantees about the amount you’re able to borrow.

How to get a mortgage in principle at Newcastle Building Society

You can get a mortgage in principle by getting in touch with one of our Mortgage Advisers. Call our advisers using the number below, or pop into your nearest branch to speak with a member of our team. 

How long does it take to get a mortgage in principle?

You can usually get a mortgage in principle within 24 hours, however this may vary depending on your lender. At Newcastle Building Society our mortgage advisers will usually be able to give you a verbal decision within one hour providing you have all the information at hand that is required.

How long is a mortgage in principle valid?

A mortgage in principle is typically valid for up to 90 days. If it expires before you need it, you can always re-apply. However, it may be best to avoid this to prevent too many credit searches damaging your credit score.

Does a mortgage in principle affect my credit score?

A mortgage in principle can affect your credit score, but not always. This will depend on whether your lender does a hard or soft search of your records.

A soft search records the credit check as simply an enquiry on your file, whereas a hard search will mark that you’ve made an application for credit. Having a lot of applications for credit on your file can discourage lenders, as it may imply you have difficulty repaying your loans.

You may want to check with your lender before applying for a mortgage in principle, to see what kind of search they’re going to conduct.  At Newcastle Building Society, we conduct a hard search of your records.

We hope you have found this guide useful, but if you need more help then don’t hesitate to get in touch with one of our Mortgage Advisers. Call our advisers using the number below. Alternatively, why not try out our mortgage affordability calculator to get an idea of how much you may be able to borrow from us. 

Your mortgage will be secured on your home. Your home may be repossessed if you do not keep up repayments on your mortgage.

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