Credit Utilisation Explained: The Number That's Hurting Your Score
Credit utilisation is one of those technical-sounding terms that hides a huge influence on your credit score. It's the second-biggest factor after payment history. And — unlike most things on your credit file — it can change overnight.
If your score is lower than you think it should be, utilisation is the first place to look. Here's what it is, how it works, and how to make it work in your favour.
What is credit utilisation?
Credit utilisation is the percentage of your available credit card limit that you're currently using. It applies to revolving credit (credit cards, store cards, charge cards) — not to fixed-term loans, mortgages or finance agreements.
The maths is simple:
Utilisation = (Total balance ÷ Total credit limit) × 100
So if you've got a credit card with a £5,000 limit and a £2,000 balance, your utilisation on that card is 40%. If you have a second card with a £3,000 limit and £600 balance, your overall utilisation across the two is (2,600 ÷ 8,000) × 100 = 32.5%.
That percentage is the bit that affects your score. The actual £ amount matters less than the ratio.
How is it calculated?
Every month (roughly), your card issuer reports your balance to the credit reference agencies. That reported balance, alongside your credit limit, is what gets used to calculate utilisation. The reporting date is usually your statement date — but not always.
Here's where a useful trick comes in: utilisation isn't an average. It's a snapshot of one specific day each month. If you pay your balance down to near zero just before your statement date, your reported utilisation can be very low — even if you spent thousands during the month and paid it all back.
This is why "I always pay in full" doesn't necessarily protect your score. If you happen to have a high balance on your statement date, that's what gets reported to the credit agencies — regardless of whether you clear it days later. For high spenders, knowing your statement date and timing payments to land before it is a real, quiet win.
Why does it matter so much?
Lenders treat high utilisation as a red flag. The reasoning goes: someone using most of their available credit is closer to financial stress than someone using a small fraction of it. Even if you've been paying every penny on time, a balance that's regularly close to your limit suggests strain.
The exact impact on your score varies between credit reference agencies, but the broad pattern is:
- 0-9% utilisation: Best for your score
- 10-29%: Still healthy
- 30-49%: Mild negative impact
- 50-74%: Significant negative impact
- 75-100%: Heavy negative impact — and lenders considering new applications often decline at this level alone
The good news? Because utilisation is a snapshot rather than an average, you can move it from "bad" to "good" within a single statement cycle just by paying down. Few credit-score factors move that fast. Our credit improvement guide ranks utilisation as one of the top three quick-wins.
What is the ideal credit utilisation rate?
Below 30% is the rule of thumb. Below 10% is where scoring models really reward you. Right down to 0% is actually slightly worse than 1-5% in some scoring models — having a tiny balance shows the card is active, which helps your file look healthy.
So if your goal is the best possible score:
- Aim for total utilisation under 10%
- Pay most of your balance off before your statement date each month
- Leave a small balance (a few pounds) showing on the statement
- Pay that off in full when the statement arrives, before the due date
This combination keeps your reported balance low and your interest costs at zero.
Does it matter per card or overall?
Both. Most credit reference models look at overall utilisation across all your cards as the headline figure. But they also look at each individual card. A single maxed-out card can drag your score down even if your overall utilisation looks healthy.
Example: you have two cards. Card A has a £1,000 limit and you've used £900 (90% utilisation). Card B has a £10,000 limit and you've used £100 (1% utilisation). Overall utilisation is £1,000 ÷ £11,000 = 9% — looks fine. But the 90% on Card A is still visible and still hurts.
The fix is to spread balances out if you can, so no single card sits near its limit. If that's not possible, prioritise paying down the maxed-out card first. Our credit card repayment calculator can help you plan the timeline.
How to lower your credit utilisation
In rough order of speed:
- Pay down a high-balance card. The fastest direct effect. Even a partial paydown moves the needle.
- Request a credit limit increase. If your lender agrees, your utilisation drops without you paying off a penny. Most do this with a soft search if you've been a customer for a while.
- Time your payments to land before the statement date. The reported balance is the one that matters.
- Spread balances across multiple cards. If one card is maxed but another has plenty of headroom, you can sometimes move spending around.
- Use a 0% balance transfer card. Move expensive balances to a new card at 0%, and as long as your old limits stay open, your overall utilisation drops while you pay it down.
For larger balances, our debt consolidation calculator can help you see whether rolling card debt into a personal loan would actually save money and improve utilisation simultaneously.
Should you close unused credit cards?
Almost always: no.
Closing a card reduces your total available credit. If you're carrying any balance at all on your other cards, your utilisation immediately rises. And the closed card's account history — which has been quietly helping your length-of-credit-history factor — drops off your file after six years.
The exception is when a card has an annual fee you're no longer earning back through rewards. In that case, the savings outweigh the score hit. Even then, expect a small temporary dip in your score.
If you're worried about fraud on a dormant card, you can usually request that the lender freeze or lower the limit rather than closing it outright. That keeps your history intact without the fraud risk.
Credit utilisation and mortgage applications
If you're applying for a mortgage in the next year, utilisation matters more than usual. Mortgage lenders see high credit card balances as a double negative: it hurts your credit score (affecting the rate they'll offer), and it raises your minimum monthly debt commitments (affecting the affordability assessment).
The smart move: spend the three to six months before your application paying down credit cards to under 30% utilisation. Lower if you can. Your reported balance on each statement date in the months leading up to the application should ideally be modest.
This isn't subtle. A maxed-out credit card in the run-up to a mortgage application can be the difference between an acceptance at 4.5% and a rejection — or an acceptance at 5.5%. Over a 25-year mortgage on £200,000, that single percentage point is roughly £40,000 in extra interest. Worth the effort.
Common myths about credit utilisation
A few persistent myths worth busting:
- "Paying off in full each month protects me." Not entirely. If your statement balance is high on the reporting date, your utilisation is high — even if you pay it off the next day.
- "Having no balance is best." Slightly worse than having a tiny balance. Some scoring models prefer evidence of active, controlled usage.
- "My utilisation only matters when I apply for credit." No — it's part of your live score and affects you whenever your file is checked.
- "Closing cards I don't use helps." Almost always the opposite. Closing reduces available credit and shortens history.
- "A higher limit means I'm in more debt." Not how lenders see it. Higher limits with low balances actually improve your score.
Get the basics right, watch your statement-date balances, and your utilisation can work for you instead of quietly working against you.
Frequently asked questions
What is the ideal credit utilisation percentage?
Below 30% is the generally accepted target. Below 10% is even better — that's the band where credit scores typically peak. So if your total credit card limit is £10,000, aim to keep total balances below £3,000, and ideally below £1,000 at the time your file is reported each month. Going right down to 0% can actually be marginally worse than 1-5%, because some scoring models reward active but light usage.
Does credit utilisation matter per card or in total?
Both. Most scoring models look at your overall utilisation across all cards as the main figure. But a single card near its limit can also drag your score down, even if your overall utilisation is healthy. The safest approach is to keep every individual card below 30% as well as the overall total.
When does my utilisation get reported?
Typically once a month, when your card issuer sends an update to the credit reference agencies. The reporting date is often (but not always) your statement date. So your reported utilisation reflects your balance on that one specific day, not your average across the month. That's why paying down a balance a few days before your statement date is often more effective than paying after.
Should I close my unused credit cards?
Usually no. Closing an unused card reduces your total available credit, which pushes your utilisation up on the cards you still use. It also shortens your average account age. If a card has no annual fee, leaving it open and using it for a small purchase every few months is the better move. Only close it if there's an annual fee you're no longer earning back, or if the card represents a fraud risk.
Does credit utilisation matter for mortgages?
Yes, significantly. Mortgage lenders see high credit card utilisation as a sign of financial stress, even if you pay in full each month. It can hurt both your credit score (affecting the rate you're offered) and your affordability assessment (high balances mean higher monthly payments in the lender's eyes). Bringing utilisation down a few months before applying is one of the highest-impact preparation steps.