If you are thinking about applying for a mortgage, your credit score is one of the most important factors a lender will consider. Understanding how credit scoring works - and what you can do to put yourself in the best position - can make a real difference to the rates and products available to you.

What is a credit score?

A credit score is a number that represents how reliable you have been as a borrower based on your past financial behaviour. It is calculated by credit reference agencies using information from your credit file - which includes details of your borrowing history, repayment record, electoral roll registration, and any negative markers such as missed payments, defaults, or county court judgments.

In the UK, the three main credit reference agencies are Experian, Equifax, and TransUnion. Each has its own scoring scale and its own way of calculating your score, which is why your score can look different depending on which agency you check. Lenders typically use one or more of these agencies when assessing your application.

How do lenders use credit scores?

Lenders use your credit file - not just the score itself - to assess the risk of lending to you. A good credit history suggests you are likely to keep up with repayments. A poor history, or no history at all, raises questions that lenders will want answered.

Your credit score influences two things: whether a lender will approve your application at all, and if they do, what interest rate they will offer you. Applicants with stronger credit histories typically have access to a wider range of products and better rates. Those with adverse credit - missed payments, defaults, or past CCJs - may find their options more limited, though specialist lenders do exist for these situations.

It is also worth knowing that lenders carry out their own internal scoring in addition to the credit reference agency data. Two lenders looking at the same applicant can reach different decisions, which is one reason why using a whole-of-market broker rather than approaching lenders directly can be valuable.

What factors affect your credit score?

Several things contribute to your credit score, and understanding them helps you know where to focus if you want to improve it.

Payment history is the biggest factor. Consistently paying bills, credit cards, and loans on time builds a positive record. Missed or late payments - even on small accounts - can have a disproportionate negative effect, particularly if they are recent.

Credit utilisation is also significant. This refers to how much of your available credit you are using. If you have a credit card with a £5,000 limit and regularly carry a balance close to that limit, it can signal financial stress even if you never miss a payment. Keeping utilisation below 30% of your available limit is generally considered good practice.

The length of your credit history matters too. Older accounts with a clean repayment record are viewed positively. Closing old accounts can sometimes reduce your average account age and have a small negative effect.

Applying for credit frequently leaves what are known as hard searches on your file. A single application has minimal impact, but multiple applications in a short period can suggest financial difficulty and may reduce your score. This is particularly relevant when shopping around for mortgages - using a broker means you can have your situation assessed without multiple hard searches being registered.

Electoral roll registration is a simple but important one. Being registered to vote at your current address helps lenders verify your identity and address history. If you are not registered, it is worth doing - it is a quick fix that can have a positive effect.

Negative markers such as defaults, county court judgments, individual voluntary arrangements, or bankruptcy stay on your credit file for six years from the date they were registered. Their impact reduces over time, particularly as they approach the six-year point, but they will be visible to lenders throughout that period.

What can you do to improve your credit score before applying for a mortgage?

The most effective steps are straightforward, though some take time to have an effect.

Check your credit file before you apply. All three agencies offer free access to your report - Experian, Equifax via ClearScore, and TransUnion via Credit Karma. Look for errors, outdated information, or accounts you do not recognise, and raise a dispute if anything looks wrong. Mistakes on credit files are not uncommon and can be corrected.

Register on the electoral roll if you have not already done so.

Pay down credit card balances where you can, and avoid making new credit applications in the months before a mortgage application.

If you have missed payments in the past, focus on building a clean record from this point forward. Consistent on-time payments over 12 to 24 months can make a meaningful difference to how lenders view your application.

If you have very little credit history - sometimes called a thin file - it can be worth building some. A credit builder card used for small purchases and cleared in full each month is one way to establish a track record without taking on significant debt.

Does a poor credit score mean I cannot get a mortgage?

Not necessarily. There are lenders who specifically cater for applicants with adverse credit, including those with missed payments, defaults, and even past CCJs. The rates on these products are typically higher to reflect the additional risk, but they can provide a route to homeownership that improves over time as the adverse markers age and your credit record improves.

A whole-of-market broker can assess your credit position and identify which lenders are most likely to consider your application - without leaving unnecessary hard searches on your file in the process.

How Aspect Mortgages can help

The team at Aspect Mortgages are independent whole-of-market advisers with access to lenders across the full market, including those who specialise in applicants with less than perfect credit histories. We will assess your situation honestly and help you understand your options before you apply.

To have a conversation about your mortgage prospects, call us on 01257 812345 or visit our mortgages page.