How long does a mortgage agreement in principle last?

A mortgage agreement in principle, also called a decision in principle or AIP, is a lender's estimate of how much they might lend you. It is not a formal mortgage offer, but it is useful proof to estate agents that you are a serious buyer.

Most agreements in principle last between 30 and 90 days. Some lenders set 30 days, others 60 or 90. The exact period depends on the lender and the product. You can usually find the expiry date on your AIP certificate or in the email the lender sent.

Why does an AIP expire? Your circumstances can change, and so can the lender's criteria and rates. After a few months, the lender wants to check that your income, credit file and deposit are still the same before they confirm the amount.

If your AIP runs out, you can usually renew it with the same lender or get a new one elsewhere. Renewal often means a fresh soft credit check, which does not affect your credit score. The broker or lender will reconfirm your income, deposit and any other details that have changed.

Try to get your AIP when you are ready to start viewing properties seriously. Having it too early means it could expire before you find a home, and having it too late means an estate agent may not book a viewing.

An expired AIP does not stop you from buying a property. It just means you need a fresh one before you make a formal application. If your offer is accepted, the lender will still need to do a full underwriting check before issuing a final mortgage offer.

If you want certainty on the day you view a home, speak to a whole-of-market broker or adviser. They can arrange multiple AIPs quickly and help you renew without repeated hard searches.

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