Credit scores feel mysterious, partly because they are produced by private companies and partly because most consumer advice about them is oversimplified. The actual scoring models — FICO and VantageScore — publish the factors and weights they use. Reading the original documentation removes most of the guesswork.
This article walks through the standard FICO scoring breakdown, what each factor really measures, and the practical actions that meaningfully move a score over months rather than weeks.
Who makes the score, and which one matters
In the US, two scoring companies dominate: FICO and VantageScore. FICO scores (versions 8, 9, and 10) are still the most commonly used by lenders, especially for mortgages, which by federal regulation often use older FICO models for the three credit bureaus (Equifax, Experian, TransUnion). VantageScore is used by some lenders and by most "free score" consumer apps.
You don't have one score — you have several, because each bureau holds slightly different data and lenders pull different models. The differences are usually small. Focus on the underlying behavior, not the specific number.
The five FICO factors and their weights
FICO publishes the five categories that go into its score and their approximate weights. Payment history is the largest at about 35%, followed by amounts owed at 30%, length of credit history at 15%, new credit (recent inquiries and accounts) at 10%, and credit mix at 10%. The weights vary slightly by individual — the documentation states they're typical for a general consumer.
- Payment history — ~35%
- Amounts owed (utilization) — ~30%
- Length of credit history — ~15%
- New credit — ~10%
- Credit mix — ~10%
Payment history
On-time payments are the single largest input. A 30-day late payment can drop a previously good score by 50–100 points and stays on the credit report for seven years (though impact fades over time). Setting at least the minimum payment to autopay on every revolving account is the highest-leverage thing most people can do.
Bankruptcies, charge-offs, collections, and foreclosures fall under payment history and are heavily weighted; their impact diminishes with time but they remain visible on the report for seven to ten years.
Amounts owed — and why "utilization" matters
This category is dominated by credit utilization: the percentage of available revolving credit you're using. The CFPB and FICO both note that keeping utilization low — generally below 30%, ideally below 10% — is associated with the highest scores. Importantly, utilization is calculated on each card and on the total across cards.
Utilization is a snapshot of what's on your statement, not a long-term average. Paying down a balance before the statement closes can move the reported utilization down within a single month.
Length of history, new credit, and credit mix
Length of credit history considers the age of your oldest account, your newest, and the average age across accounts. Closing a long-held card can shorten the average and slightly hurt the score, especially if it was your oldest. New credit measures recent applications; multiple inquiries in a short period can drop the score temporarily, though FICO groups multiple mortgage or auto-loan inquiries within a short window as a single shop.
Credit mix rewards having a mix of revolving (cards) and installment (auto, mortgage, student) accounts. It's a small factor and not worth opening accounts you don't need.
What's not in the score
Income is not in the FICO score, though lenders consider it separately when underwriting a loan. Checking-account balances, employer, age, race, religion, marital status, and national origin are explicitly excluded by the Equal Credit Opportunity Act. Soft inquiries (your own credit checks, prequalified offers) don't affect the score.
Disputes that result in inaccurate information being removed do change the score. Reviewing your free annual reports at AnnualCreditReport.com — the only site authorized by federal law — is the fastest way to catch errors.