When starting your search for a new property, one of the first steps is securing a mortgage in principle. But what exactly is a mortgage in principle? How do you get one? And how can it help you in your home-buying journey? Discover all the essential information about mortgages in principle in our detailed guide.
What is an agreement in principle?
An agreement in principle (AIP), also called a mortgage in principle or decision in principle, is an estimate from a lender (like a bank or building society) of how much they might lend you. You can get an AIP if you are:
To get an AIP, you need to provide the lender with some basic information:
Your personal details (name, date of birth, nationality).
Your address history for the last three years.
Your contact details (phone number and email).
Your financial details (income, monthly expenses, loans),
You might also need to estimate the value of the property you’re interested in and how much you can pay as a deposit. At this stage, you don’t need to provide documents like bank statements.
Is an agreement in principle the same as a mortgage offer?
An agreement in principle (AIP) differs from a full mortgage offer:
With an agreement in principle, you give the lender some basic financial details, and they provide an estimate of how much they might lend you.
A full mortgage offer is an official and detailed agreement from the lender confirming exactly how much they’ll lend you to buy your new home.
When you’re ready to make an offer on a property, you can apply for a mortgage. You’ll need to provide documents like bank statements and payslips at this stage. The lender will then carry out detailed checks, including a full credit check, before informing you of the amount they can lend you.
How long does a mortgage in principle last?
When you receive an agreement in principle from a lender, it typically remains valid for 30 to 90 days. This allows you plenty of time to explore properties. If you don’t find the ideal property within this timeframe, or if the agreement expires before your offer is accepted, you can easily renew it or apply for a new one.
You may need to get a new agreement in principle if any of your details or circumstances change. This includes any changes to your income, spending habits or debt.
What do lenders consider when you apply for a mortgage in principle?
When you apply for an AIP, mortgage lenders carefully review your financial situation. This helps them understand what you can comfortably afford. Here’s what they’ll usually consider:
Your income – How much you earn, whether from employment, pensions or other sources.
Your monthly outgoings – This includes regular expenses like rent or mortgage payments, utility bills and childcare costs.
The property’s value – An estimated cost of the home you’re hoping to buy.
Your deposit – The amount you’re able to put down upfront.
Your planned retirement age – This helps lenders work out how long your mortgage term could last.
Other properties – If you own or have mortgages for other properties, this will be taken into account.
Loans and credit – Any outstanding loans or credit card balances will be taken into consideration.
The lender uses this information to estimate how much they could lend you. Having an AIP is helpful when looking at properties because it shows sellers and estate agents that you’re financially ready to buy.
Here and ready when you are
Whether you have questions about a specific kind of mortgage or just want to find out more, the expert team are on hand to help.
A mortgage in principle is not a guaranteed mortgage offer – it’s just an indication of how much you could borrow. You’ll still need to complete the full mortgage application process when you decide to make an offer on a property.
Because things can change between getting your AIP and applying for a mortgage, there’s always a chance the outcome might be different. A full credit check may reveal new financial details, and if you used estimates for your income, debts or the property’s value, the lender might reassess your application. They may also update their lending criteria, which could affect how much they’re willing to offer.
How do I get a mortgage in principle?
You can get a mortgage in principle online. Visit your preferred lender’s website, fill out the form, and you could get one in minutes. Alternatively, you can visit their branch in person. Most lenders offer this service for free.
It’s also possible to get a mortgage in principle via a mortgage broker. They can see what deals are available across the market, helping you find the best interest rates.
What happens after you receive a decision in principle?
Once a lender has given you a mortgage in principle, you’ll have a clearer idea of your budget. This means you can start exploring the property market with confidence. Take your time browsing listings and attending viewings until you find a home that feels right for you.
When you’re ready to make an offer, you’ll need to start a full mortgage application. A mortgage in principle is a helpful first step, but it won’t secure the property on its own. You can apply with the same lender or choose a different one if you prefer.
If you’re aged 55 or over, there are later life mortgage options available. These are designed to support borrowing into retirement, giving you more flexibility as your financial circumstances change.
Can I get more than one mortgage in principle?
You can get a mortgage in principle from different lenders. If the first lender doesn’t offer a big enough loan or you find a better rate, you can try another option.
Does an agreement in principle affect my credit score?
When you get an agreement in principle, lenders conduct a soft credit check. This doesn’t affect your credit score because there are no visible traces left on your file by a soft credit check.
But when you apply for a full mortgage, a hard credit check is done. This could impact your credit score and leave a footprint on your credit report.
How likely is my mortgage to be approved after an agreement in principle?
Having an AIP can strengthen your position when applying for a mortgage, but it’s not a guarantee that your mortgage application will be approved. A full mortgage application requires a more detailed review of your finances, which can sometimes result in a different outcome.
At this stage, lenders will carry out a full credit check. This may reveal issues that weren’t flagged during the AIP process. Your financial circumstances may have changed since you first applied, which could affect your eligibility.
In some cases, the lender may not agree with the property valuation. If they believe the property is worth less than the price you’ve offered, it could impact the amount they’re willing to lend.
Important
Your home may be repossessed if you fail to repay your mortgage. Saga Money may receive payment from Tembo if you get a mortgage offer via the Saga Mortgages service. This will not affect the amount you pay for the service.
Saga is a registered trading name of Saga Personal Finance Limited, which is registered in England and Wales (company number 3023493). Registered office 3 Pancras Square, London, N1C 4AG. Saga Personal Finance Limited is authorised and regulated by the Financial Conduct Authority under the registration number 178922.
Tembo Money Limited (12631312) is a company registered in England and Wales with its registered office at 18 Crucifix Lane, London, SE1 3JW. Tembo is authorised and regulated by the Financial Conduct Authority under the registration number 952652. Tembo Money was awarded Best Mortgage Broker at the British bank awards in 2022, 2023, 2024 and 2025.
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