Your credit score is one of the key factors lenders consider when deciding whether to approve your mortgage and what interest rate to offer. A higher credit score gives you access to better deals and a wider range of lenders. A poor score can mean higher rates, stricter terms, or outright rejection.
The good news is that your credit score is not fixed. With the right actions, most people can improve their score significantly within 3 to 12 months. This guide walks you through every step, in priority order, so you are in the strongest possible position when you apply.
Step 1: Check Your Credit Reports
1 Get reports from all three agencies
The UK has three main credit reference agencies: Experian, Equifax, and TransUnion. Each holds slightly different information, and different lenders check different agencies. You need to review all three to get the full picture.
You can check your reports for free using:
- Experian: Free Experian account (limited) or MSE Credit Club
- Equifax: ClearScore (free, updated weekly)
- TransUnion: Credit Karma (free)
When reviewing your reports, look for: errors in your personal details (name, address, date of birth), accounts you do not recognise, missed payments that you believe were made on time, and old addresses or financial associations with ex-partners.
Step 2: Fix Any Errors
2 Dispute inaccuracies immediately
Errors on credit reports are surprisingly common. Incorrect addresses, duplicate accounts, and wrongly recorded missed payments can all drag your score down unfairly. If you find an error, raise a dispute directly with the credit reference agency. They are legally required to investigate within 28 days.
If the dispute is not resolved in your favour but you believe you are right, you can add a "Notice of Correction" to your file — a short statement (up to 200 words) explaining the circumstances. Lenders must consider this when reviewing your application.
Step 3: Register on the Electoral Roll
3 This is the single quickest credit score boost
Being registered on the electoral roll at your current address is one of the most important factors in your credit score. It confirms your identity and address, which lenders use to verify who you are. If you are not registered, your score takes a significant hit.
Register at gov.uk/register-to-vote. It takes about 5 minutes and the effect on your credit score can be seen within weeks. If you are not eligible to vote (for example, as a non-UK/Commonwealth/EU citizen), you can send proof of residency directly to the credit agencies instead.
Step 4: Reduce Credit Utilisation
4 Keep credit card balances below 30% of your limit
Credit utilisation — the percentage of your available credit that you are using — is a major factor in your score. If you have a credit card with a £5,000 limit and a £4,500 balance, your utilisation is 90%, which is very damaging.
Aim to keep utilisation below 30% across all cards. Below 10% is even better. You can reduce utilisation by paying down balances, or by requesting a credit limit increase (but only if you will not be tempted to spend more — and do not do this within 6 months of your mortgage application).
Step 5: Close Unused Credit Accounts
5 Too much available credit can work against you
While having some credit history is important, having too many open credit accounts — even if they have zero balances — can count against you. Mortgage lenders look at your total available credit as potential debt. If you have five credit cards with a combined limit of £25,000, a lender may factor that into their affordability calculation even if the balances are zero.
Close accounts you no longer use, keeping one or two active cards that you use regularly and pay off in full. Do this well in advance of applying (at least 3 months), as closing accounts can cause a temporary dip in your score.
Step 6: Build a Positive Credit History
6 Use credit responsibly and consistently
Paradoxically, having no credit history at all can be worse than having a small amount of well-managed debt. Lenders want evidence that you can borrow responsibly and repay on time.
If you have a thin credit file, consider using a credit card for small regular purchases (fuel, groceries) and paying the balance in full every month by direct debit. This builds a track record of reliable repayment without costing you any interest.
If you have been refused credit cards due to a poor score, a credit-builder card (offered by providers like Aqua, Vanquis, or Capital One) can help. These come with higher interest rates, but if you pay in full each month, you pay no interest.
Step 7: Avoid New Credit Applications
7 Stop applying for credit 6 months before your mortgage
Every time you apply for credit (credit card, loan, phone contract, car finance), a "hard search" is recorded on your credit file. Multiple hard searches in a short period signal to lenders that you may be financially stretched or desperately seeking credit — both red flags for mortgage underwriters.
From 6 months before you plan to apply for a mortgage, avoid all new credit applications. This includes buy-now-pay-later services (Klarna, Clearpay, etc.), which increasingly appear on credit files and can affect your mortgage application.
Step 8: Remove Financial Associations
8 Unlink yourself from ex-partners with poor credit
If you have ever had a joint account, joint mortgage, or joint bill with someone, you are financially associated with them on your credit file. Their credit behaviour can affect your score. If that person has poor credit, this association can drag your score down.
If the joint financial product no longer exists, contact each credit agency and request a "notice of disassociation". This removes the link and ensures their credit history no longer affects yours.
Step 9: Pay All Bills on Time
9 Set up direct debits for everything
Payment history is the most heavily weighted factor in your credit score. Even one missed payment can cause a significant drop and stay on your file for 6 years. Set up direct debits for at least the minimum payment on all credit accounts, and for all regular bills (phone, utilities, council tax).
If you are struggling to make payments, contact the creditor before missing a payment. Many will offer a payment plan or temporary reduction. A negotiated arrangement looks far better on your credit file than a missed payment.
How Long Does It Take?
| Action | Time to See Impact |
|---|---|
| Register on electoral roll | 1–4 weeks |
| Fix errors on credit report | 28 days (investigation period) |
| Reduce credit utilisation | 1–2 months (after statement dates) |
| Close unused accounts | 1–3 months |
| Build positive history | 3–6 months minimum |
| Missed payments dropping off | 6 years from the date of the missed payment |
| CCJs/defaults dropping off | 6 years from the date registered |
| Bankruptcy removal | 6 years from the date of discharge |
What Credit Score Do I Need for a Mortgage?
There is no single "minimum credit score" for a mortgage because each lender uses its own scoring system and criteria. However, as a rough guide:
- Excellent (Experian 961–999): Access to the best rates from all lenders
- Good (Experian 881–960): Most lenders will approve you, competitive rates available
- Fair (Experian 721–880): Many lenders will consider you, but rates will be higher
- Poor (Experian 561–720): Limited options, specialist lenders, higher rates
- Very poor (Experian 0–560): Very few lenders, may need to improve score before applying
Remember that your credit score is just one factor. Lenders also consider your income, employment stability, deposit size, existing debts, and the property itself. A slightly lower credit score combined with a large deposit and stable income may still result in approval.
Related Guides
- Mortgage Application Guide — what happens when you apply
- First-Time Buyer Checklist — complete buying plan
- How Much Deposit Do I Need? — deposit sizes and sources
- Mortgage Glossary — all mortgage terms explained