Credit Utilization Calculator
Calculate your credit utilization ratio and its impact on your credit score.
What this calculator does
This credit utilisation calculator shows how much of your available revolving credit you are using, where that places you against the bands lenders work to, and precisely what you would need to repay to hit a target ratio. Enter your total credit limit, your current balance, and the utilisation percentage you are aiming for.
Utilisation is the fastest-moving element of a UK credit file. Payment history builds over years and account age cannot be accelerated, but utilisation reflects whatever balance was reported on your last statement. That makes it the one thing you can meaningfully change ahead of a deadline.
When to use it
The most valuable moment is one to two months before a mortgage application or a car finance agreement. Balances report on statement dates, so a paydown made now appears in the file a lender searches next month, and moving from 40 percent to under 25 percent can shift which rate tier you are offered.
It is also worth running after a large purchase on a card and after any balance transfer, since moving £5,000 onto a card with a £6,000 limit produces 83 percent utilisation on that account even though your total debt has not changed. And check it before closing a card you no longer use — the calculator shows what losing that limit does to the ratio.
Understanding the inputs
Total credit limit is the sum of limits across all revolving accounts: credit cards, store cards, and any card-based credit lines. Loans, car finance, and mortgages are instalment debt and are assessed separately, so leave them out.
Current balance should be the figure reported to the credit reference agencies, which is usually your statement balance rather than the live figure in your banking app. Target utilisation is where you want to land — 30 percent is the standard guideline, 25 percent is where Experian starts rating usage as excellent, and single digits is where the strongest files sit.
How is this calculated?
Utilization Ratio = (Total Balances / Total Limits) × 100. Keep below 30% for good credit; below 10% for excellent.
A worked example
Take £9,000 of total limits across two credit cards with £3,600 outstanding. That is 40 percent utilisation, well above the 30 percent guideline of £2,700 — so £900 above the threshold before you even think about a target.
Aiming for 25 percent means a target balance of £2,250 and a paydown of £1,350, leaving £6,750 of unused capacity. Now suppose you close the smaller card with a £3,000 limit while carrying that £3,600. Total limits fall to £6,000 and utilisation jumps to 60 percent, on exactly the same debt. Closing unused cards is one of the more common self-inflicted credit file injuries.
Limitations and assumptions
Utilisation is one component among several, alongside payment history, the age of your accounts, recent searches, and whether you are on the electoral roll — which UK lenders check and which matters more than many people realise. A low ratio does not offset a recent default or a very thin file.
The calculator uses aggregate utilisation and does not model per-card ratios, which some scoring models weigh separately. Experian, Equifax, and TransUnion also score on different scales with different data, so treat the rating band shown as directional. The reliable principle is simply that a lower reported balance always reads better than a higher one.
Common Questions
- What is a good credit utilisation ratio in the UK?
- Under 30 percent is the usual guidance and under 25 percent is where Experian in particular starts treating your usage as excellent. There is no cliff edge — the relationship is gradual, so any reduction improves how lenders read your file, and single-digit utilisation is where the strongest applications sit.
- Do all three credit reference agencies treat it the same?
- Broadly, but not identically. Experian, Equifax, and TransUnion each produce their own score on their own scale, and lenders often check only one. They also hold different data, because not every lender reports to all three. It is worth checking your file with each rather than assuming one score represents you.
- When is my balance reported?
- Most UK card issuers report the statement balance monthly, so the figure lenders see is what was outstanding on your statement date rather than what you owe today. Paying a few days before the statement closes, rather than by the due date, is what changes the reported figure — and it can move within one cycle.
- Does a 0% purchase or balance transfer card still count?
- Yes. Utilisation is about how much of your available credit is in use, not what rate you are paying on it. A £5,000 balance on a 0 percent deal weighs exactly the same as a £5,000 balance at 24.9 percent, which catches out people who transfer a large balance onto a card with a modest limit.
- Should I close credit cards I no longer use?
- Usually not. Closing an account removes its limit from your available credit, so the same balances become a higher percentage. Dormant accounts also contribute account age, which helps. Some issuers close inactive cards themselves after a year or two, so a small transaction occasionally keeps them alive.
- Does an overdraft count toward utilisation?
- Overdrafts are reported to the credit reference agencies and lenders do look at persistent use, though whether they feed a utilisation calculation depends on the scoring model. Regardless of the arithmetic, sustained overdraft use is read as a sign that outgoings exceed income and weighs against mortgage applications specifically.
- Does buy now pay later affect my credit file?
- Increasingly yes. Klarna and other providers began reporting to UK credit reference agencies from 2022, so BNPL balances and missed payments can appear on your file. They are not always treated as revolving credit for utilisation purposes, but mortgage lenders reading your statements will notice them either way.
- How quickly does paying down a balance help?
- Within one reporting cycle, typically 30 days. Utilisation carries no history in scoring models — they use the currently reported balance. That makes it the fastest lever available, and the reason to act one to two months before a mortgage or car finance application rather than the week before.
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- Debt Payoff CalculatorSee how quickly you can clear your debts using avalanche or snowball strategies, and compare total interest.