A FICO score is one brand of credit score. Lenders use it to estimate how likely you are to repay a loan. People often say "FICO" when they mean credit scores in general, but the two are not the same thing. The Consumer Financial Protection Bureau (CFPB) describes a credit score as a number that predicts how likely you are to pay a loan back on time, based on the information in your credit report. FICO, the company formerly known as Fair Isaac Corporation, makes one of the best-known formulas for that prediction.

How the Score Is Calculated

A scoring model is a mathematical formula. It takes the raw data in your credit report and turns it into one number. Most credit scores run from 300 to 850. Base FICO Scores use that range, while industry-specific versions run from 250 to 900. Several versions exist, so the number you see depends on which one is applied. According to myFICO, FICO Score 8 is the base version most widely used by lenders.

The formula looks at several kinds of information. FICO lists five categories: payment history, amount of debt, length of credit history, credit mix, and new credit. The CFPB describes a similar set in plainer terms. It names your bill-paying history, your current unpaid debt, the number and type of loan accounts you have, how long your accounts have been open, how much of your available credit you use, and recent applications for credit. It also lists collections, foreclosures and bankruptcies, and how long ago they happened.

None of this is fixed. Pay a bill on time or pay down a card, and the inputs change. The score is a snapshot of your file on the day it is requested.

Who Uses It and Why

Lenders are the main users. The CFPB says companies use credit scores for mortgage and credit card decisions, auto loans, tenant screening and insurance. They also use them to set interest rates and credit limits. Some FICO versions may be used by Fannie Mae, Freddie Mac or others to help decide eligibility for home lending.

FICO says its scores are used by 90% of top lenders. That figure comes from FICO's own materials and a study of all the FICO versions it sells to lenders. It is not an independent count, so treat it as the company's claim.

Some versions are built for one job. The FICO Auto Score and the FICO Bankcard Score are tuned to predict risk for car loans and credit cards. A lender or insurer may also use a different FICO version than the one you were shown. It may use a different credit score altogether.

Why Your Number May Differ

You do not have one credit score. You have many. Experian, TransUnion and Equifax each keep a file on you, and those files can hold slightly different information. A FICO Score is based on the file from a given agency at the time it was requested. So the same model can return different results from different bureaus.

Date matters too. A score pulled last month may not match one pulled today. The CFPB says scores can differ by the data used, the scoring model, the data source and the calculation date. FICO also states that other credit scores can differ from FICO Scores by up to 100 points. That is FICO's own statement, but it fits the general point: different models give different numbers.

The lender chooses which score to use. You cannot assume the number you see is the one they will pull.

A tilted brass balance scale, reading glasses, and a folded statement on a sunlit wooden desk, suggesting how a single credit figure can shift depending on what is being weighed.
A brass balance scale tips beside reading glasses and a folded statement, a picture of how one credit figure can shift with what goes on the scale.

Questions to Ask and Red Flags

If a lender or insurer quotes you a score, ask three things. Which FICO version or other score did you use? Which credit reporting agency's file did you pull? When was the score calculated? The answers explain most gaps between two numbers.

You also have rights over the file itself. The CFPB notes you can request and review a free credit report every year. Nationwide credit reporting companies must freeze and unfreeze your credit reports for free on request.

Be wary of any site that sells a score as a guaranteed result. The sources describe scores as predictions that vary by model, data and date, so no one can promise the exact figure a lender will see. For general scam awareness, the Federal Trade Commission has a consumer page on credit scores.

Please seek a professional. This article is general information, not financial, tax or insurance advice. Please seek a licensed financial, tax or insurance professional about your own situation.