It might not be the most exciting part of buying a home, but understanding your budget before you start viewing can save you time, help you make informed decisions and put you in a stronger position when you find somewhere you want to buy.

At Mortlock & Joyce, we regularly speak to buyers who are just starting their property search. While it's tempting to jump straight onto Rightmove and book a few viewings, getting your finances in order first can make the whole process much smoother.

A mortgage agreement in principle (AIP), sometimes called a decision in principle or mortgage in principle, is an indication from a mortgage lender of how much they may be prepared to lend you, based on the information you've provided. It usually takes into account factors such as your income, regular expenditure, existing debts and credit history, although the checks carried out will vary between lenders. It's important to understand that an agreement in principle is not a formal mortgage offer. The lender will still need to carry out further checks, assess the property you want to buy and confirm that you meet its lending criteria before approving your mortgage. However, it gives you a useful starting point and helps you understand what you may be able to afford.

One of the biggest advantages of having an agreement in principle is knowing where you stand financially. It's easy to browse properties online and find homes that catch your eye, but the asking price is only one part of the equation. You also need to consider your deposit, legal fees, survey costs, moving expenses and ongoing mortgage payments. An AIP can help establish a realistic price range, allowing you to focus on properties that are more likely to be within your budget. For example, if you're looking at properties around £350,000 but your borrowing capacity and deposit mean a more realistic budget is £300,000, it's better to know that before you start arranging viewings. It can also help you understand whether you need to adjust your expectations, increase your deposit or speak to a mortgage adviser about your options. Remember, just because a lender indicates that you could borrow a certain amount doesn't mean you should borrow the maximum available. Your monthly repayments need to be comfortable and sustainable for your circumstances.

Good properties can attract interest quickly, particularly when they're priced realistically and appeal to a wide range of buyers. If you find somewhere you want to make an offer on, having an agreement in principle already in place means you've taken an important step towards demonstrating that you are financially prepared. Without one, you may need to arrange the necessary checks before you can confidently proceed, potentially putting you on the back foot if another buyer is ready to move forward. An AIP doesn't guarantee that your offer will be accepted, but it can help show the seller and estate agent that you've taken your finances seriously. In a competitive situation, being organised can make a difference.

When you register with an estate agent, you may be asked whether you have a mortgage agreement in principle or whether you've spoken to a mortgage adviser. This isn't simply about ticking a box. It helps the agent understand your buying position and how prepared you are to proceed. For example, there's a difference between someone who has just started browsing properties without knowing their budget and someone who has an agreed budget, a deposit ready and a clear understanding of their mortgage options. If you're buying with a mortgage, an AIP is a useful part of demonstrating that preparation. It also helps the agent recommend suitable properties rather than arranging viewings that are unlikely to be financially realistic. At Mortlock & Joyce, we want buyers to find the right property, but we also want them to be in a position to move forward when they do.

An agreement in principle gives you an early indication of your potential borrowing, which can help you decide how much to offer on a property. However, there are a few things to remember.

First, the lender's initial assessment is based on the information available at that stage. Your final borrowing could change following a full application. Second, the property itself matters. A lender will usually carry out a valuation as part of the mortgage application, and if the valuation comes in below the agreed purchase price, you may need to renegotiate or find additional funds. Third, your budget should account for your deposit and other buying costs, not just the amount a lender may be prepared to lend. Having an AIP is a useful starting point, but it shouldn't be treated as a guarantee that the lender will approve a particular property or mortgage amount.

This is a common question, and the answer depends on the lender and the type of credit check it carries out. Some lenders use a soft credit search when providing an agreement in principle, which generally won't affect your credit score in the same way as a hard search. Others may carry out a hard credit search, which can be visible to other lenders. Before applying, ask whether the lender will use a soft or hard search and whether it could affect your credit file. If you're using a mortgage broker, they can help you understand which lenders may be suitable for your circumstances and explain the process before an application is made. It's also worth avoiding multiple unnecessary applications, particularly if you're unsure which lender is right for you.

An agreement in principle commonly lasts between 60 and 90 days, although this varies by lender. If you're planning to buy soon, it can make sense to arrange one before you begin viewing properties. If you're still several months away from buying, you may prefer to speak to a mortgage adviser first and arrange the AIP closer to when you're ready to start making offers. If your agreement expires before you find a property, you can usually apply to renew it, subject to the lender's requirements and any updated checks. The key is to make sure your agreement is current when you need it.

For first-time buyers, getting an agreement in principle can be particularly useful. Buying your first home involves plenty of new terminology, paperwork and decisions, and it can be difficult to know where to start. An AIP helps establish your potential budget before you begin viewing properties. It also gives you an opportunity to discuss your deposit, mortgage options and monthly repayments with a professional. You may discover that you're able to consider a wider range of properties than expected, or that you need to save a little longer before taking the next step. Either way, having that information early can help you plan realistically. If you're buying jointly, both applicants will generally need to provide information about their finances as part of the assessment.

Yes. An agreement in principle is not a legal requirement for viewing a property, and individual estate agents may have different procedures. You may be able to arrange an initial viewing without one, particularly if you're still exploring the market. However, if you're serious about buying, it's sensible to get your finances in order early rather than waiting until you've found a property you want to offer on. That way, you can spend your time viewing suitable homes and move forward with greater confidence when the right one comes along.

If you're thinking about buying a property, our advice is simple: speak to a mortgage adviser and get an agreement in principle in place before you start seriously viewing homes.

It helps you understand your budget, makes the buying process more straightforward and puts you in a better position to act when you find the right property.

It doesn't guarantee that you'll get a mortgage, and it shouldn't be treated as a commitment to borrow. But it's a sensible first step that can make a real difference to how prepared you are.

And remember, your budget should be based on what you can comfortably afford, not simply the maximum amount a lender is willing to offer.