What Is a Credit Utilization Ratio — and Why Does 30% Matter?

One number does more to move your score than almost anything else

If there's a single ratio worth memorizing in personal finance, it's your credit utilization ratio — the share of your available credit that you're actually using. Alongside payment history, it's the most influential factor in your FICO® Score that you can change quickly. Pay it down this month and the improvement can show up the next.

The ratio, in plain English

Utilization is your balances divided by your limits. If you have a combined $10,000 in credit limits across your cards and you carry $2,000 in balances, your utilization is 20%. FICO looks at this both per card and overall — both matter.

The widely cited guideline: keep it under 30%. Under 10% is even better for top-tier scores. Per FICO's published guidance, people with the highest scores tend to use a small fraction of their available credit.

Why 30%?

Thirty percent isn't magic — it's the threshold below which statistically the risk of default drops sharply, which the scoring models reflect. Above 30%, the models read you as more reliant on borrowed money; above 50% or 70%, the penalty steepens.

Five ways to lower it (without necessarily spending less)

• Pay before the statement closes. Card issuers typically report your balance on the statement closing date, not the due date. Paying mid-cycle means a lower balance gets reported.
• Ask for a limit increase. A higher limit shrinks the ratio for the same spending — but only if you don't also raise your balances.
• Keep old cards open. Closing a card removes its limit from the denominator, instantly raising your utilization. (See our piece on credit-card myths.)
• Spread spending across cards. A high balance on one card can hurt even if your overall utilization is low, because per-card utilization counts too.
• Add a positive tradeline like rent reporting. It doesn't lower utilization directly, but a thicker, healthier file offsets the impact of a temporary balance spike.

Bottom line: of the five factors in your FICO® Score, utilization is the lever you can pull fastest. Get it under 30% — ideally under 10% — and keep it there.