The 5 Factors That Build a FICO Score

FICO publishes the high-level breakdown of its scoring formula. The five factors that produce a FICO score, in declining weight order, are:

Payment history (35%)
Amounts owed / utilization (30%)
Length of credit history (15%)
Credit mix (10%)
New credit / inquiries (10%)

Those percentages are useful as a starting point, but they're averages across the U.S. consumer population. For any individual consumer, the relative weight shifts depending on what's in the file. This post walks through what each factor actually measures, how it's calculated, and what moves the needle.

This is educational. None of it is financial advice.

Factor 1: Payment history (35%)

Payment history is the largest factor. It captures whether you've paid your accounts on time, and when you've been late, how late and how often.

What's included:

On-time payments on every reported account
Late payments (30, 60, 90, 120+ days late)
Charge-offs
Collections
Public records (bankruptcies; civil judgments and most tax liens were removed from major bureau reports in 2017)
Foreclosures
Settled-for-less-than-full accounts

What's NOT included:

Utility bills (unless the utility reports — most don't)
Rent payments (unless you opt into a service like Experian Boost or RentBureau)
Cell-phone bills paid on time

The biggest move under this factor: a single 30-day late payment can drop a high score by 60-100 points. The same late payment on a low score may have less impact (because the file already includes negative history). FICO smooths this through its scoring buckets.

What hurts most:

Recent lates (last 12 months hurt more than older lates)
Higher severity (90+ days hurts more than 30 days)
Frequency (multiple lates compound)
Collections within the past 24 months

What helps:

Consistent on-time payments across all accounts
Time elapsed since the last negative
"Goodwill" letters that occasionally lead to deletion of an isolated late

Factor 2: Amounts owed / utilization (30%)

This factor measures how much credit you're using relative to how much credit you have available. It's the second-largest factor and the one most directly under your control month-to-month.

The headline metric: revolving utilization. Revolving utilization = (current credit-card balances) / (current credit limits) × 100%.

The "30% rule" is convention, not statute. FICO has confirmed that lower utilization scores better, and the steepest scoring benefit is below 10%. A consumer at 9% utilization scores higher than one at 29% utilization, who scores higher than one at 49% utilization, etc.

A few specifics:

Per-card utilization matters too. If your overall utilization is 20% but one specific card is at 95%, the high-utilization card drags your score even with a healthy aggregate. Spreading balances across cards (when possible) helps.

Statement-date balances are what FICO sees. Your card issuer reports your balance to the bureaus once per month, typically on the statement closing date. Even if you pay in full by the due date, the score reflects the statement-date balance. Paying down before the statement closes — not just before the due date — is what shows lower utilization.

Installment-loan utilization matters but less. Mortgages, auto loans, and personal loans contribute to total amounts owed, but they're weighted less than revolving utilization. A high mortgage balance doesn't hurt the way a high credit-card balance does.

Closing cards reduces total available credit and can spike utilization. If you have $10,000 total credit across cards and you close a card with $3,000 limit, your total drops to $7,000. The same $2,000 balance is now 28.5% utilization instead of 20%.

What helps:

Pay down balances before statement closing dates
Spread balances across cards (when possible) to lower per-card utilization
Request credit-limit increases (without taking new credit) to expand denominators

Factor 3: Length of credit history (15%)

This factor measures how long your accounts have been open and how long it's been since you last used them.

What's included:

Age of your oldest account
Average age of all accounts
Age of newest account
Time since last activity on each account

A consumer with a single 25-year-old card and three 2-year-old cards has an oldest-account age of 25, an average age of around 7, and a newest-account age of 2.

This factor is one of the slowest to improve. Time is the only fix. Two practical implications:

Don't close old cards lightly. Closing an old card doesn't remove it from your report immediately (closed accounts age out over 7-10 years), but the average-age denominator shrinks when you eventually drop closed accounts.

Authorized-user history can boost age. Being added to an aged authorized-user account can move your average-age metric quickly. Removing yourself later loses that boost.

Factor 4: Credit mix (10%)

FICO scores reward a mix of revolving (credit cards) and installment (loans) credit. A consumer with five credit cards and no installment loans scores lower under this factor than one with three credit cards and an auto loan.

This factor is small (10%) and not worth taking on debt to improve. If you happen to have a mortgage, an auto loan, and credit cards, your mix is fine. If you only have credit cards, opening a credit-builder loan (small installment loan from a credit union) can move this factor — but only at the margin.

Categories of credit:

Revolving: credit cards, store cards, lines of credit
Installment: auto loans, mortgages, personal loans, student loans
Open: charge cards (some American Express cards, requires payment in full each month)

Factor 5: New credit / inquiries (10%)

This factor measures your recent credit-seeking activity:

Number of recent hard inquiries (within the past 12 months)
Number of recently opened accounts
Time since the most recent account opened

Hard inquiries vs. soft inquiries:

A "hard inquiry" happens when a lender pulls your credit for a credit decision (a new card, a loan, an apartment). Hard inquiries appear on your report for 24 months and affect your score for 12 months. A single hard inquiry typically drops a score by 5-10 points.

A "soft inquiry" happens when you check your own score, when a lender pre-approves you for a marketing offer, or when an employer runs a background check. Soft inquiries don't affect your score.

The "shopping window" exception:

When you're rate-shopping for a mortgage, auto loan, or student loan, FICO consolidates multiple inquiries within a 14-45 day window into a single inquiry for scoring purposes. This means you can shop multiple lenders without being penalized 5-10 points per pull.

The window is 14 days for older FICO models (used in some mortgage decisions) and 45 days for newer models. To be safe, finish your rate-shopping within 14 days.

How the factors interact

The 35-30-15-10-10 weights are averages. For any specific consumer:

A consumer with several recent late payments is mostly affected by Factor 1, with the others mattering less
A consumer with maxed-out cards but perfect payment history is mostly affected by Factor 2
A young consumer with limited history is heavily affected by Factor 3
A consumer who recently opened five new cards in 60 days will see Factor 5 dominate their score temporarily

The implication: focus on the factor that's most broken for your specific file. A consumer trying to improve a 580 score should look at what's actually pulling the score down (almost always payment history or collections at that level), not micromanage a credit-mix ratio.

What can move scores fastest

If you need to move a score quickly (e.g., before a mortgage application):

Fastest moves (30-60 days):

Pay down credit-card balances before statement dates
Dispute and remove inaccurate negative items
Become an authorized user on a high-quality, aged card
Have a 30-day late removed via a goodwill letter

Medium-speed moves (3-6 months):

Open a small installment loan to improve credit mix
Request credit-limit increases on existing cards
Wait out a recent hard inquiry's impact

Slow moves (12+ months):

Build payment history on new accounts
Wait for collections to age past their reporting limit
Build account age organically

Sources cited

FICO consumer education — https://www.myfico.com/credit-education
VantageScore — https://vantagescore.com
CFPB credit scores guidance — https://www.consumerfinance.gov/consumer-tools/credit-reports-and-scores/
AnnualCreditReport.com — https://www.annualcreditreport.com

Educational content. FICO model versions update periodically. Cite specific situations to a credit-repair attorney for legal interpretation.