What Is FICO Score?
A FICO score is a credit score developed by Fair Isaac Corporation, used in over 90% of U.S. lending decisions. Scores range from 300 to 850, calculated from five weighted categories: payment history (35%), amounts owed (30%), length of credit history (15%), credit mix (10%), and new credit (10%). Multiple versions exist — mortgage lenders use older versions (FICO 2, 4, or 5), while credit cards typically use FICO 8.
Key Facts
- FICO scores are used in over 90% of U.S. lending decisions, making Fair Isaac Corporation's algorithm the most consequential scoring model in consumer finance
- There are over 50 different FICO score versions in use — mortgage lenders use FICO 2 (Experian), FICO 4 (TransUnion), and FICO 5 (Equifax), which are older versions that may differ from FICO 8 or 9
- FICO announced the FICO 10 and FICO 10T (trended data) models in 2020, and FHFA mandated their adoption for conforming mortgages starting in late 2025
- The five scoring categories create clear optimization targets: payment history (35%) and credit utilization (30%) together account for nearly two-thirds of the score
- Average FICO scores vary significantly by age group — consumers 60+ average above 750, while those under 30 average around 660, reflecting shorter credit histories and less established payment records
How Are FICO Scores Calculated?
FICO's algorithm evaluates five categories from data in your credit report:
- Payment history (35%): Whether you've paid on time. This is the single most impactful category. Late payments, collections, and public records (bankruptcies) all damage this category.
- Amounts owed (30%): How much of your available credit you're using. High credit utilization — especially above 30% on revolving accounts — signals higher default risk.
- Length of credit history (15%): How long your accounts have been open. Longer credit history generally produces higher scores, which is why closing old accounts can be counterproductive.
- Credit mix (10%): The variety of credit types — revolving (credit cards), installment (mortgages, auto loans), and open accounts. A diverse mix indicates experience managing different credit types.
- New credit (10%): Recent credit applications and account openings. Multiple new accounts or inquiries in a short period suggest higher risk, except when rate shopping for a single loan type.
The exact algorithm is proprietary, but the weights are published and the general logic is well-documented. FICO recalibrates its models periodically using large datasets of actual consumer payment behavior.
Why Are There So Many FICO Score Versions?
FICO has released numerous score versions since the original model in 1989. Key versions include:
- FICO 2, 4, 5: The classic mortgage scoring versions, still mandated by Fannie Mae and Freddie Mac for conforming loans. Being phased out.
- FICO 8: The most widely used version for auto loans and credit cards. Introduced in 2009 with changes to how isolated late payments and authorized user accounts are treated.
- FICO 9: Reduced the penalty for medical collections. Not widely adopted by mortgage lenders.
- FICO 10 and 10T: The newest versions. FICO 10T uses trended data — analyzing 24 months of payment patterns rather than a single snapshot. FHFA has mandated adoption for GSE-backed mortgages.
The version proliferation creates a practical problem: the score you see on Credit Karma (typically VantageScore 3.0) or your bank app (often FICO 8) may differ substantially from the score your mortgage lender uses (FICO 2/4/5). Differences of 20–40 points between versions are common.
How Does the FICO Score Connect to Financial Distress?
The FICO score is the mechanism through which the American Distress Index's indicators translate into individual borrower outcomes. When the ADI registers rising delinquency rates, those delinquencies flow through FICO's payment history category (35% of the score) to produce lower scores, which trigger higher rates, reduced access, and deeper financial strain. The FICO score doesn't just measure distress — it amplifies it through a feedback loop of worsening terms on subsequent borrowing.
Frequently Asked Questions
What is the difference between FICO and VantageScore?
FICO is used in 90%+ of lending decisions and has been the standard since 1989. VantageScore was created in 2006 by the three bureaus as a competitor. Key differences: VantageScore can score consumers with shorter credit histories, weights factors slightly differently, and uses a 14-day rate shopping window vs. FICO's 45-day window. For mortgage applications, FICO is what matters.
Which FICO score version does my mortgage lender use?
Currently, most mortgage lenders use FICO 2 (Experian), FICO 4 (TransUnion), and FICO 5 (Equifax). They pull all three and use the middle score. FHFA mandated the transition to FICO 10T for conforming loans backed by Fannie Mae and Freddie Mac — this transition is underway as of late 2025.
Why is the FICO score on my credit card app different from my mortgage score?
Your credit card app likely shows FICO 8 or VantageScore 3.0, while mortgage lenders use FICO 2/4/5. These different versions weight the same data differently, resulting in scores that can vary by 20–40 points. The mortgage-specific versions tend to be more conservative and may produce lower scores.
What is the minimum FICO score to get a mortgage?
For conventional loans: typically 620, with the best rates at 740+. For FHA loans: 580 with 3.5% down, or 500 with 10% down. For VA loans: no official minimum, but most lenders require 620. For USDA loans: typically 640. These are industry standards, not regulatory requirements — individual lender overlays may be stricter.
How quickly can I improve my FICO score?
The fastest improvement comes from reducing credit utilization — paying down credit card balances can show results within 30 days when the lower balance is reported. Other factors take longer: late payments diminish in impact over 12–24 months, and building a longer credit history is inherently gradual. There is no legitimate way to achieve overnight improvements.