Three bureaus, three separate files
Equifax, Experian, and TransUnion are independent companies. They don't share data with each other in real time. Each bureau maintains its own credit file on you, and those files are built from whatever information creditors choose to send them.
Your FICO score at Experian is calculated from Experian's data. Your FICO score at Equifax is calculated from Equifax's data. They use the same scoring formula, but if the underlying data is different, the scores will be different.
Reason 1: Creditors don't report to all three bureaus
This is the most common reason for score differences. Most major creditors — banks, card issuers, auto lenders — report to all three bureaus. But not all creditors do.
Some smaller lenders, credit unions, medical billing services, and local financial institutions report to only one or two bureaus. If a positive account (say, a credit union loan you've paid perfectly for three years) only reports to Equifax, your Equifax score will be higher than your Experian score, which doesn't see that account at all.
Similarly, a negative item — a collection, a late payment — might only appear on one bureau if the creditor or collector doesn't report to all three. A collection agency that only reports to TransUnion will drag down your TransUnion score without affecting Equifax or Experian.
Reason 2: Reporting timing is not synchronized
Even when a creditor reports to all three bureaus, they don't necessarily update all three on the same day. A balance change on your credit card might be reflected in your Experian report on the 5th, but not in your Equifax report until the 12th. During that window, your scores will differ.
This is especially noticeable after you pay down a large balance or open a new account. The update will ripple through the bureaus at different times.
Reason 3: Different scoring model versions
When you check your score through different services, you may be looking at different versions of the FICO scoring model — or different scoring models entirely.
- FICO 8 is the most widely used model for credit decisions
- FICO 9 is used by some lenders
- VantageScore 3.0 and 4.0 are used heavily by free monitoring services
The same person can have meaningfully different scores under FICO 8 versus VantageScore 3.0 because the two models weigh factors differently. Medical collections, for example, are treated differently across models.
When comparing scores across services, make sure you're comparing the same model version and the same bureau. Comparing your FICO 8 at Experian to your VantageScore at Equifax is comparing apples to oranges.
Reason 4: Errors unique to one bureau
Sometimes one bureau has incorrect information that the others don't have. A creditor may have reported an error to one bureau only, or a mixed file issue may only affect one bureau's records.
If you have a 30-point gap between two bureaus that can't be explained by known account differences, it's worth pulling the reports side by side and looking for discrepancies: an account that appears on one but not others, a balance that differs, a late payment that appears on one bureau's version but not another's.
A legitimate data error on one bureau that doesn't appear on the others is a disputeable inaccuracy.
What a "normal" gap looks like
Score differences of 20–40 points between bureaus are not uncommon and usually reflect legitimate data differences. Differences above 50 points warrant closer inspection.
What lenders see
When you apply for a mortgage, the lender pulls all three bureaus and uses your middle score — not the highest, not the lowest, but the one in the middle. For a joint application, they use the lower of the two applicants' middle scores.
For auto loans and credit cards, lenders typically pull one or two bureaus. Which bureau they use varies by lender and sometimes by region. This means your score at the bureau they pull is the one that matters for that decision — even if your scores at the other two bureaus are higher.
The action worth taking
Pull all three reports from AnnualCreditReport.com and compare them side by side. Identify any account, balance, or payment history item that appears differently across bureaus. If you find a genuine inaccuracy on one bureau's version, dispute it with that bureau directly. Correcting the data gap narrows your score spread.