Early in your home-buying journey you will hear about getting a mortgage in principle, and you may wonder what it is and whether you need one. It is a useful, often essential, first step. This guide explains what a mortgage in principle is, how to get one, and why it matters.
What a mortgage in principle is
A mortgage in principle, also called a decision in principle or agreement in principle, is a statement from a lender indicating how much they might be willing to lend you, based on some initial information about your income and circumstances. It is not a formal mortgage offer or a guarantee, but it gives you a realistic idea of your budget and shows others you are a credible buyer. It is usually free and quick to obtain.
How it works
To get a mortgage in principle, you give a lender or broker details about your income, outgoings, deposit and the kind of property you want. The lender carries out some checks, often including a soft credit check that does not affect your credit score, and tells you how much they would consider lending in principle. The whole process can often be completed quickly, sometimes within minutes online or with a broker's help.
Why you need one
A mortgage in principle matters for two main reasons. First, it tells you how much you can realistically borrow, so you can house-hunt within budget rather than falling for homes you cannot finance. Second, it shows estate agents and sellers that you are a serious, credible buyer who can proceed, which can strengthen your position when making an offer. In competitive markets, having one ready can make a real difference.
Soft and hard credit checks
Most mortgage in principle checks are soft searches, which are visible only to you and do not affect your credit score, so getting one, or even a few, does no harm. A full mortgage application later involves a hard search, which is recorded and can be seen by lenders. Knowing the difference reassures you that obtaining a mortgage in principle is a safe, sensible step that will not damage your credit.
How long it lasts
A mortgage in principle is typically valid for a limited period, often around 30 to 90 days, after which it may expire and need renewing. This matters because house-hunting can take time. If yours expires before you find a home, you can usually renew it. Keeping it current means you are always ready to make an offer with evidence that you can secure the finance, which sellers and agents like to see.
It is not a guarantee
It is important to understand that a mortgage in principle is not a guaranteed mortgage offer. The lender still has to carry out full checks when you formally apply, including verifying your income, assessing the specific property, and a full credit search. A mortgage in principle can be followed by a declined application if something does not check out. So treat it as a strong indication, not a certainty, and keep your finances in good order.
How it fits into buying
Getting a mortgage in principle is one of the early steps in buying a home, ideally before you start viewing seriously, as our guide to buying your first home step by step explains. It follows working out how much you can borrow, as our guide to how much you can borrow covers, and precedes making offers and applying formally for the mortgage.
What information you need
To get a mortgage in principle, you typically provide details of your income, employment, outgoings, any debts, your deposit and the kind of property and price you have in mind, plus personal details for the credit check. Having this information to hand makes the process quick. The more accurate the details you give, the more reliable the figure you receive, so it is worth being precise rather than rough with your numbers.
Mortgage in principle versus mortgage offer
It is important not to confuse a mortgage in principle with a full mortgage offer. The mortgage in principle is an early, indicative figure based on limited checks. A mortgage offer comes later, after a full application, detailed checks, income verification and a property valuation, and is the lender's firm commitment to lend. The mortgage in principle gets you house-hunting; the mortgage offer is what actually finances your purchase.
Can it be declined later?
Yes, having a mortgage in principle does not guarantee your full application will succeed. The lender may decline at the full application stage if something does not match, such as income that cannot be verified, an issue on a full credit search, or a property the lender will not lend against. This is why you should keep your finances stable between getting a mortgage in principle and completing, and avoid taking on new credit.
Using it to make an offer
When you find a home, having a mortgage in principle strengthens your offer, because it shows the estate agent and seller that you can finance the purchase. In a competitive situation, a buyer with a mortgage in principle ready can be preferred over one without. Some estate agents ask to see it before putting your offer forward, so having it in place keeps you ready to act when the right home comes up.
Renewing or getting another
If your mortgage in principle expires before you buy, you can usually renew it or get a new one. If your circumstances have changed, the figure might change too. Getting a mortgage in principle from a different lender is also fine and, because most use soft searches, doing so does not harm your credit. So you are free to keep yours current and to shop around as your search continues.
Soft searches mean no harm in checking
Because most mortgage in principle checks are soft searches, there is no downside to getting one early, and little harm in getting more than one as your search develops. This lets you start house-hunting with a clear, evidenced budget and the credibility that sellers value, without any worry about your credit record. Treating the mortgage in principle as a routine first step sets you up well for everything that follows.
A sensible, low-risk first step
In short, getting a mortgage in principle is a sensible, low-risk first move that costs nothing, usually leaves your credit untouched, and gives you both a realistic budget and credibility with sellers. It is one of the easiest ways to start your home-buying journey on the front foot, so it is well worth doing early, before you begin viewing homes in earnest, and keeping it current as your search goes on.
In short
A mortgage in principle is a lender's indication of how much they might lend you, based on initial checks, usually involving a soft credit search that does not affect your score. It tells you your realistic budget and shows sellers you are a serious buyer, which strengthens your offers. It is not a guaranteed offer and lasts a limited time, but getting one early is a sensible and usually essential first step.
Where to get help and next steps
Read our guides to how much a first-time buyer can borrow and buying your first home step by step. This is general information, not mortgage or financial advice.