What Determines Your Credit Score? The 5 Factors, Ranked by Weight

Payment history (~35%) — by far the biggest piece

Whether you’ve paid your bills on time is the single heaviest factor in most credit scoring models, commonly cited around 35% of a FICO score. This covers every account that reports to the bureaus — credit cards, auto loans, student loans, even some phone and utility accounts if they report. A single late payment usually isn’t reported until it’s about 30 days past due, but once it hits that mark it can knock a meaningful chunk off your score, and the damage gets worse the longer it goes unpaid (30, 60, 90+ days are tracked separately and hit harder each step). A bankruptcy or an account sent to collections is the most severe version of this category and can weigh on your score for years.

There’s no trick here — the entire category is just "did you pay what you owed, when you owed it." Automating minimum payments on every account is the single highest-leverage thing you can do for your score.

Amounts owed / credit utilization (~30%) — how much of your limit you’re using

This category looks at how much of your available revolving credit you’re actually using, most importantly your overall credit utilization ratio: total balances divided by total credit limits, across all your cards. The commonly cited rule of thumb is to stay under 30% utilization, and under 10% is generally considered even better for a top-tier score. The catch most people miss: this number is usually calculated from whatever balance is sitting on your account on your statement closing date — not whether you carry a balance month to month or pay it off in full. You can pay your card off completely every month and still show high utilization if you happened to charge a lot right before the statement cut.

If your utilization looks high, paying down the balance before the statement closes (not just before the due date) is the fastest lever you have.

Length of credit history (~15%) — why this one just takes time

This factor looks at the age of your oldest account, the age of your newest account, and the average age across all of them. It’s the one category you genuinely cannot rush — there’s no strategy that substitutes for time. This is also exactly why teenagers and young adults tend to have lower scores than older adults with identical payment habits: it’s not a penalty for anything you did wrong, it’s just math based on how long your file has existed.

The practical takeaway: keep your oldest account open, even if you stop using it regularly. Closing your first-ever credit card doesn’t erase its history immediately, but it will eventually stop counting toward your average age once it drops off your report — quietly working against a factor you spent years building.

Credit mix (~10%) — small, and not worth forcing

Scoring models give a modest amount of credit for successfully managing different types of credit — revolving accounts (credit cards) and installment accounts (auto loans, student loans, a credit builder loan) at the same time. It shows a scoring model that you can handle more than one kind of obligation responsibly.

Because this is only about 10% of the total score, it’s not worth taking out a loan you don’t need or paying interest on debt purely to "diversify" your file. If you naturally end up with a mix — a credit card plus a student loan, say — you’ll get some credit for it. Chasing this factor on its own is usually not worth the cost.

New credit (~10%) — recent inquiries and freshly opened accounts

This category tracks how many hard inquiries you’ve had recently and how many new accounts you’ve opened. Each hard inquiry (applying for a real card or loan, not checking your own score) typically costs somewhere around five points, and opening several new accounts in a short window can look risky to a lender even if each individual application was reasonable on its own. This is the smallest of the five factors, and its effect on your score fades well before the inquiry itself disappears from your report.

Spacing out applications — rather than applying for multiple cards in the same month — keeps this category from dragging on an otherwise strong file.

Your checklist

1. Automate at least the minimum payment on every account — payment history is worth more than every other factor combined, roughly speaking. 2. Pay down credit card balances before the statement closing date, not just before the due date, to lower reported utilization. 3. Keep your oldest account open, even unused, to protect your average length of credit history. 4. Don’t open a loan or card purely to "improve your mix" — it’s a 10% factor, not worth paying interest for. 5. Space out new credit applications by a few months instead of applying for several accounts back-to-back. 6. Check your full credit report (not just your score) at least once a year for errors — a mistake in any of these categories can drag your score down for reasons that aren’t actually your fault.