What is an Agreement in Principle?

An Agreement in Principle (AIP) is a personalised indication of how much you may be able to borrow towards the purchase or remortgage of a property. It's sometimes known as a 'Mortgage in Principle', a 'Decision in Principle' or a 'mortgage promise'.
  • It has no impact on your credit score.
  • There's no commitment to get a NatWest mortgage and you don't need to be a NatWest customer already.
  • It's free and takes less than ten minutes to complete.

How would I get an Agreement in Principle certificate?

  • An Agreement in Principle (AIP) certificate is a document that you can use with an estate agent, or someone selling a property, to show that you may be in a financial position to purchase it.
  • Having your certificate to hand could be useful when trying to secure house viewings, which may speed up your home buying journey.
  • To get a certificate, you'll first need to get a positive Agreement in Principle decision. Once you have this, you can download your AIP certificate.

What happens after you have an Agreement in Principle?

Once you have an AIP you can save your details so, when it's time, it's easy for you to apply.

You can apply online by retrieving your saved application or completing a new one. Then, select the mortgage you want and begin your mortgage application.

Or, if you'd like support, we're on hand to arrange a phone or video appointment with one of our qualified mortgage professionals. 

Call us on ${dn-0800 096 9527} Opening hours

Relay UK: 18001 0800 096 9527

When should I get an Agreement in Principle?

  • It is useful to have an AIP when you are viewing properties with an intention to buy, or when you are looking to remortgage a property.
  • It provides an estate agent, or seller, with confidence that you may be in a financial position to purchase a property.
  • If your circumstances change, you should get an updated Agreement in Principle (often called a 'Mortgage in Principle').

Does an AIP effect my credit score?

Getting an AIP doesn't impact your credit score, as we don't run a 'full' credit check. This is only something we would run if you went on to apply for a mortgage with us.

Is an AIP different to a mortgage calculator?

Yes. A mortgage calculator is a great way to get a quick idea of how much you may be able to borrow, but it's not as personalised. Your AIP is also a formal document that you can use when you're considering on making an offer for a property.

Can I get an AIP if I've struggled financially in the past?

If you've had money problems before, it doesn't necessarily mean you can't get an AIP. Once you've provided some information to us about your circumstances, we'll be able to give you an indication of whether we may be able to lend to you, and how much you might be able to borrow. 

  • If you do decide to apply for a mortgage with us, we will run a full credit check, and use this information to help inform our decision to lend.
  • Therefore, it is a good idea to consider potential factors that may impact or improve your credit score, before you are in the position of applying for a mortgage.

Find out more about credit score when applying for a mortgage

Can I get more than one AIP?

Yes, you can have multiple Agreement in Principles. Having an AIP with NatWest doesn't stop you getting another from a different lender. However, if you do have one with us, you can request a fresh one whenever you need to.

Does an AIP mean I'll definitely be able to get a mortgage?

No, a mortgage AIP is an indication that we may be able to lend you a certain amount towards the purchase or remortgage of a property.

However, as part of a full mortgage application, we complete a number of other more detailed checks, including a full credit check. We use this information, alongside other criteria, to help inform how much we could formally be able to offer.

How are the details I give for an AIP used?

As part of the application, we will ask for some personal information about you and your circumstances. We use this to help personalise the indication of how much you may be able to borrow.

  • We won't use your contact details to contact you about anything other than your AIP, unless you explicitly opt in to get more communications from us.
  • As part of the application, we may provide your details to certain third parties, such as credit reference agencies, to help validate the information you give us and prevent fraud. We will not run a full credit check, and your credit score will not be impacted.
  • For more information about how we may use your personal information, and your rights in relation to personal information, please see our Privacy Policy.

A few more frequently asked questions

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