Of the five things FICO measures, “amounts owed” is the second-biggest — 30% of your score. Most of that subcategory comes down to one number: utilization. It’s the simplest ratio in personal finance, and the one most surrounded by bad advice.
What utilization is
Utilization is the share of your available revolving credit you’re using at the moment your balance is reported. Two flavors:
- Per-card utilization. Balance on one card divided by that card’s limit.
- Total utilization. Sum of all card balances divided by sum of all card limits.
If you have one card with a $5,000 limit and a $1,000 balance, you’re at 20% utilization on that card and on your overall revolving credit.
The number that’s reported is the balance on your statement closing date, not the balance the day you pay it off. This matters: many people pay their statement balance in full and still show high utilization, because the balance was high when the statement closed.
Why 30% became the rule of thumb
Somewhere in the late 1990s, FICO researchers began publishing aggregate statistics: borrowers with utilization above 30% defaulted at noticeably higher rates than those below. Personal-finance columnists rounded this to “keep your utilization under 30%,” and the number stuck.
The trouble is that 30% isn’t the goal. It’s the level above which the score starts to take real damage. Going from 28% to 22% gives you almost nothing; the score curve flattens sharply on the low end.
What high scorers actually do
FICO publishes profile statistics for the highest-scoring borrowers. Their median utilization is about 4%. Their average is closer to 7%. The biggest difference between “good” scores (700–750) and “exceptional” scores (800+) is rarely income, age, or sophistication — it’s usually utilization, plus length of history.
Two practical moves that compound:
- Pay before the statement closes, not just by the due date. The reported balance drops, and so does utilization, even though you’re paying the same amount.
- Spread spending across cards. Two cards at 10% each show better than one card at 20%, even though the dollar balance is identical. (Per-card and overall both factor in.)
If you want a deeper map of how the score is built, our explainer on what a credit score actually measures walks through the full five-factor breakdown.
Sources & further reading
- 01What’s in my FICO Scores. myFICO.com · 2024
- 02Credit reports and scores. Consumer Financial Protection Bureau · 2024