TransUnion uses both FICO and VantageScore. The question of whether TransUnion uses FICO or VantageScore has a “both” answer because TransUnion isn’t a scoring company at all: it’s a credit bureau that stores your financial history and licenses that data to two separate scoring companies, FICO and VantageScore. When a lender or app asks TransUnion for a score, the bureau can deliver either one, and the same TransUnion file can produce dozens of different scores depending on which model and version gets applied.
TransUnion Is the Data, Not the Score
TransUnion is a data warehouse. It tracks your open and closed accounts, balances, payment history, and public records like bankruptcies, then sells that information to lenders and other businesses that need to evaluate credit risk.1TransUnion. What to Look for in Your Credit Report FICO and VantageScore are separate companies. Each one builds its own mathematical models that convert credit-bureau data into three-digit scores. TransUnion has licensing agreements with both, so a lender pulling your TransUnion file can request a FICO score, a VantageScore, or in some cases several of them.
That’s why “which score does TransUnion use” is the wrong framing. The bureau supplies the raw data; whoever’s checking your credit picks the model. You could have a FICO Score 8 of 705 and a VantageScore 3.0 of 740 sitting on the exact same TransUnion file at the exact same moment. Neither is wrong.
The Score You See on Free Apps Is Usually VantageScore
Most free credit monitoring platforms, including TransUnion’s own free service, show you a VantageScore 3.0.2TransUnion. Free Credit Monitoring Credit Karma and Credit Sesame do the same. So when someone says “my TransUnion score is 740,” they’re almost always quoting a VantageScore, because that’s what the free tools display.
Meanwhile, most lenders use some version of FICO for actual lending decisions. FICO says 90% of top lenders use FICO Scores. That gap between what you check at home and what a lender sees is where confusion sets in: you walk into an application expecting one number and see a different one on the approval paperwork.
Some credit card issuers and banks provide a free FICO Score on monthly statements. If you have that, it’ll be closer to what a lender actually pulls. Comparing the two side by side tells you how much the model choice matters for your specific credit profile.
Which Score Lenders Actually Pull
The lender picks the scoring model. You don’t. Different industries have settled into different preferences.
Mortgage lenders have historically relied on FICO models because Fannie Mae and Freddie Mac required them. Auto lenders frequently use industry-specific FICO Auto Scores that emphasize car-loan repayment. Credit card issuers are mixed: some use FICO Score 8, others have adopted VantageScore, particularly for applicants with shorter credit histories.
The practical effect: a borrower with a paid medical collection on their TransUnion file could look great under VantageScore 4.0 and mediocre under FICO Score 8. The model choice can influence whether you’re approved, what rate you receive, and whether you need a co-signer. You can’t control which model a lender picks, but you can ask before applying. Some will tell you.
Why the Same File Produces Different Numbers
The most common general-purpose models pulled against TransUnion data include FICO Score 8, FICO Score 9, FICO Score 10T, VantageScore 3.0, and VantageScore 4.0. Each version weighs your credit data differently, and a few specific differences drive most of the gap you’ll see between them.
Medical Debt
This is one of the sharpest dividing lines. VantageScore 3.0 and 4.0 exclude medical collection accounts entirely, whether paid, unpaid, large, or small.3VantageScore. VantageScore Removes Medical Debt Collection Records From Latest Scoring Models VantageScore estimates this can boost affected consumers’ scores by up to 20 points.
FICO 9 and 10 reduce the weight of unpaid medical collections and ignore paid ones. FICO Score 8, still the most commonly used version in lending, does neither. Under FICO 8, a paid medical collection still drags your score down, and an unpaid one hits as hard as any other collection. If medical collections sit on your TransUnion file, the scoring model matters enormously.
Trended Data
VantageScore 4.0 and FICO 10T both use trended data, tracking how your balances and payment behavior shift over time rather than looking at one snapshot. Paying down a card steadily over six months helps you under these newer models in a way FICO Score 8 can’t reflect. FICO claims 10T can expand mortgage approval rates by up to 5% without adding risk.4FICO. FICO Score 10T for Mortgage Originations
Thin Credit Files
VantageScore can score consumers with very thin files, sometimes just a month or two of history. Older FICO versions typically need at least six months of activity before generating a score. If you’re new to credit, a free VantageScore might show a number when a FICO pull comes back unscorable.
The Mortgage Situation Is Changing
Mortgage lending has been going through a scoring shakeup that directly involves TransUnion data. For years, Fannie Mae and Freddie Mac required lenders to pull Classic FICO scores from all three bureaus in a tri-merge report.
The Federal Housing Finance Agency has validated both FICO 10T and VantageScore 4.0 for mortgage underwriting.5FHFA. Credit Scores As of July 2025, FHFA announced that lenders selling loans to the government-sponsored enterprises can use either VantageScore 4.0 or Classic FICO.6Fannie Mae. Credit Score Models and Reports Initiative A larger planned change requiring lenders to deliver both FICO 10T and VantageScore 4.0 on every loan was postponed from its original fourth-quarter 2025 target to a date not yet set.
FHFA also plans to allow bi-merge reports pulling from two bureaus instead of three, which could lower borrower costs. That implementation was also pushed back to align with the FICO 10T transition.7FHFA. FHFA Announces Key Updates for Implementation of Enterprise Credit Score Requirements For now, expect mortgage lenders to pull Classic FICO from TransUnion alongside the other two bureaus, with VantageScore 4.0 as an available option.
Where to Check Your TransUnion Score
TransUnion offers a free credit monitoring account called Credit Essentials with a daily VantageScore 3.0 and access to your TransUnion credit report at no charge.2TransUnion. Free Credit Monitoring Paid tiers add features like identity theft insurance and dark web monitoring. Credit Karma and Credit Sesame also provide free TransUnion VantageScores, monetized through product recommendations rather than fees.
For your full report without a score, federal law entitles you to a free copy from TransUnion through AnnualCreditReport.com.8Office of the Law Revision Counsel. 15 USC 1681j – Charges for Certain Disclosures The three bureaus have permanently extended a program that lets you pull each bureau’s report once per week for free through that site.9Consumer Advice. You Now Have Permanent Access to Free Weekly Credit Reports These reports show the raw data but don’t include a score. For an actual FICO Score, you’ll typically use a free monitoring service that offers one or pay through myfico.com.
Fixing the Data Underneath
Because your TransUnion file feeds every score generated from it, an error in the underlying data corrupts every model’s output at once. Federal law requires TransUnion to follow reasonable procedures to ensure maximum possible accuracy of the information in your file.10Office of the Law Revision Counsel. 15 USC 1681e – Compliance Procedures Checking your report through the free weekly access is the easiest way to catch problems early.
You can dispute errors online through TransUnion’s website, by phone, or by mail. For written disputes, the address is TransUnion Consumer Solutions, P.O. Box 2000, Chester, PA 19016-2000.11TransUnion. Dispute Your Credit Report by Mail or Phone Include your name, date of birth, Social Security number, the company that reported the disputed item, the partial account number, and your reason.
TransUnion generally has 30 days to investigate, extending to 45 days in certain circumstances, then five business days to notify you of the results.12Consumer Financial Protection Bureau. How Long Does It Take to Repair an Error on a Credit Report If the bureau sides against you and you still believe there’s an error, you can file a complaint with the Consumer Financial Protection Bureau.13Consumer Financial Protection Bureau. What if I Disagree With the Results of My Credit Report Dispute Fixing the data at TransUnion fixes every FICO and VantageScore built on top of it.