Credit & Credit ScoresIntermediate5 min read

FICO score versions, explained

FICO 8, 9, 10, 10T — and why your mortgage lender may still use a model from over a decade ago.

Saying 'my FICO score' is like saying 'my phone's operating system' without a version number. FICO has released many versions over the years — 8, 9, 10, 10T and, for specific industries, tuned variants — and they don't all score you the same way. More surprising: newer isn't automatically what lenders use. Mortgage underwriting, in particular, has long relied on FICO versions that predate the smartphone. Knowing which version a lender pulls explains why your 'score' can be three different numbers on the same day.

Why there are multiple versions at all

FICO periodically rebuilds its model to reflect how borrowers actually behave and to improve its prediction of who will default. Each rebuild is a new version. But lenders don't upgrade in lockstep — swapping the score that underwrites billions in loans is a slow, regulated, expensive process. So at any given moment, different lenders are running different vintages of FICO, and you effectively have several valid FICO scores simultaneously.

Version	Rough theme
FICO 8	Long the most widely used general-purpose version
FICO 9	Softened treatment of paid collections and medical debt
FICO 10 / 10T	10T adds 'trended data' — your balance patterns over time
Industry scores	Auto and card versions tuned to those specific risks

A simplified lineage. The headline is that adoption lags release — old versions stay in heavy use for years.

Newer ≠ what's used

The existence of FICO 10 does not mean lenders use it. Adoption lags release by years, and some corners of lending (notably mortgages) have historically used much older versions. The version that matters is the one your specific lender pulls.

What 'trended data' changed

Older FICO versions largely take a snapshot: what's your balance and utilization right now? FICO 10T and other trended-data models look at the pattern over the past couple of years — are your balances trending up or down, do you pay in full or carry and grow debt? Two people at the same 40% utilization today can score differently if one has been climbing toward it and the other has been paying down. For a chronic revolver, trended data can hurt; for someone steadily deleveraging, it can help. It rewards the direction you're heading, not just where you stand.

Same file, three FICOs

Ben pulls a FICO 8 from his credit card issuer: 742. He applies for a mortgage and the lender pulls older mortgage-industry FICOs across the bureaus, taking the middle number: 731. His new-car dealer runs a FICO Auto Score: 755, because that model weighs his flawless auto-loan history more heavily. Three legitimate FICO scores, one unchanged report. He didn't get better or worse between Tuesday and Thursday — different versions simply read him differently.

What to do about it

1
Ask which version before a major loan
For a mortgage or auto loan, the specific FICO version and bureau drive your rate. Ask the lender, or check a source that shows the relevant version, rather than assuming your free number applies.
2
Optimize fundamentals, not a version
Every FICO version rewards on-time payments and low utilization. You can't tune yourself to one version, but strong fundamentals lift all of them.
3
Mind trended data if you carry balances
Under newer models, a steady downward balance trend helps and a rising one hurts. Paying down consistently over months — not just before a statement — is what these models reward.

Don't chase a number you can't see

You generally can't pick which FICO version a lender uses, and buying every version to compare rarely changes your actions. Spend the energy on the report instead — clean data and low, falling balances improve you across every version at once.

The bottom line

There is no single FICO score. Versions 8, 9, 10, 10T and industry-tuned variants coexist, and lenders often run older ones — especially in mortgages. Newer models add trended data, rewarding the direction of your balances over time. Don't try to game a version; keep payments perfect and balances low and falling, and every FICO reads you well.

Check your understanding

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Why might a mortgage lender score you lower than your credit card's FICO 8 readout?

Not quite — try again.

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