Key Takeaways

• FICO® Score 4 is the TransUnion version of the classic FICO Score, formally called TransUnion FICO Risk Score, Classic 04. It is one of three scores on a mortgage tri-merge report.
• Fannie Mae’s current requirements call for classic FICO scores — Experian Score 2, TransUnion Score 4, and Equifax Score 5 — when underwriting loans through Desktop Underwriter or manually. 
• FICO Score 4 and TransUnion's ResidentScore both run on TransUnion data but answer different questions. FICO Score 4 predicts loan default; ResidentScore predicts eviction risk on a 350–850 scale.
• Because it predates FICO Score 8, FICO Score 4 counts small collections, paid collections, and medical debt that newer models discount or ignore.
• Approved lenders may now deliver conforming loans scored with VantageScore 4.0. Classic FICO remains the requirement for lenders outside that program.

What Is FICO Score 4?

FICO Score 4 is the classic FICO Score calculated from TransUnion credit data. Its formal name is TransUnion FICO® Risk Score, Classic 04, and it shows up on tri-merge reports labeled as "TransUnion/FICO Classic (04)."

The score ranges from 300 to 850 and is designed to predict the likelihood of serious delinquency. What distinguishes it is vintage and mandate: it was built on an earlier FICO modeling generation and has stayed in production because Fannie Mae and Freddie Mac required it for conforming loans.

Soft Pull Solutions serves mortgage lenders, brokers, and property managers who need the specific model their investor or screening workflow depends on.

Where FICO Score 4 Fits in the Tri-Merge

FICO Score 4 is the TransUnion component of the classic mortgage tri-merge. A lender receives it as part of a three-score report, alongside the Experian and Equifax versions of classic FICO.

That means a borrower's TransUnion score is only one piece of the mortgage credit picture. The lender compares all three bureau scores and uses the middle score as the qualifying score. For example, scores of 742, 715, and 698 result in a qualifying score of 715.

For a joint application, the calculation happens separately for each borrower. The lender takes the middle score for each person and then uses the lower of the two for the application.

Fannie Mae's Selling Guide requires lenders to obtain these classic FICO scores from each approved score provider when ordering the merged report.

FICO Score 4 vs. ResidentScore: Same Bureau, Different Question

Comparing FICO Score 4 versus ResidentScore is an important distinction to make because both models run on TransUnion data, and people assume that makes them comparable. It does not.

TransUnion reports that ResidentScore predicts evictions more accurately than a standard credit score in the highest-risk ranges. That is the entire design rationale — a model tuned to rent payment behavior rather than loan repayment.

The two can diverge sharply on the same person. An applicant with strong credit card management but a history of late rent can post a high FICO score and a much lower ResidentScore. The reverse also happens: someone carrying medical collections but paying rent reliably for six years often looks better on the rental model.

For property managers, the operational takeaway is that a 620 threshold means different things depending on which model your vendor returns. Confirm that before setting policy. Landlords running tenant screening also need to remember that eviction records generally reach a credit score only if they became a collection or judgment — a separate eviction search is what surfaces housing court filings.

And regardless of model, an adverse decision based on a consumer report triggers Fair Credit Reporting Act (FCRA) adverse action notice obligations. That applies to rental denials, not just credit denials.

Why FICO Score 4 Runs Below a Borrower's App Score

Lenders may find themselves explaining why the scores they run vary from what the borrower sees in their app. FICO Score 4 predates FICO Score 8 by more than a decade, and the differences show up on damaged files:

• Small collections count. FICO Score 8 ignores collections with an original balance under $100. FICO Score 4 applies no floor.
• Paid collections still count. FICO Score 9 stopped counting collections marked as paid. Classic models kept counting them, which means paying off an old collection may not move a mortgage score at all.
• Medical debt is not always discounted. Newer FICO models reduce the weight of medical collections; classic models do not distinguish them. The bureaus' removal of paid medical collections and those under $500 in 2022–2023 narrowed this in practice, but whatever remains on file typically counts.

A gap between a borrower's FICO Score 8 and their FICO Score 4 is normal. Files carrying collections or public records tend to sit lower on the classic model.

What Changes as Mortgage Scoring Modernizes

Classic FICO is no longer the only path for conforming loans. Approved lenders may deliver loans to Fannie Mae and Freddie Mac scored with VantageScore 4.0, and FICO Score 10T is approved for future use. Everyone else continues on classic FICO tri-merge.

We covered the rollout in VantageScore 4.0 Approved for Fannie, Freddie & FHA.

Working With FICO Score 4

Keep these best practices in mind when using FICO Score 4: 

• Pull the model that decides the file. Reports through Soft Pull Solutions can be configured to return the scoring model your investor or screening workflow requires, with multiple scores on one report when a deal is being shopped.
• Prequalify before the inquiry. A full file soft pull returns the same tradelines, balances, and derogatory detail as a hard inquiry, with nothing recorded on the consumer's file. For mortgage specifically, that also delays the trigger-lead solicitations a hard pull sets off.
• Keep the pull compliant. Permissible purpose and documented consent are required under the FCRA before any pull, and adverse action requirements attach to denials and less favorable terms alike. A compliance dashboard that logs consent and generates notices keeps the audit trail intact.

Pull the score that actually decides the file. Soft Pull Solutions delivers full credit reports and FICO® Scores through a soft pull — tri-bureau data, no SSN required, no impact on the consumer's credit. Schedule a demo or call (844) 515-1550.

Frequently Asked Questions

What does FICO Score 4 represent in a mortgage credit report?
FICO Score 4 is the TransUnion component of the traditional mortgage tri-merge. It is evaluated with FICO Score 2 from Experian and FICO Score 5 from Equifax.

What is TransUnion FICO Risk Score, Classic 04?
TransUnion FICO Risk Score, Classic 04 is the formal name associated with FICO Score 4. Different report providers may display slightly different labels for the same model.

Is FICO Score 4 the same as TransUnion ResidentScore?
No. Both use TransUnion data, but they serve different purposes. FICO Score 4 was designed to assess credit risk for lending, while ResidentScore is designed to predict rental outcomes, including eviction risk.

Which model should a property manager use for tenant screening?
That depends on the screening provider and the purpose of the screening. Property managers should confirm which scoring model their vendor returns rather than assuming a TransUnion-based score is automatically comparable to FICO Score 4.

Why might FICO Score 4 be useful during mortgage prequalification?
Because it is one of the classic scores used in the mortgage tri-merge, reviewing it before a hard inquiry can give lenders an earlier indication of how the borrower's file may perform under the applicable scoring framework.

What should lenders know about the future of FICO Score 4?
Classic FICO remains relevant for lenders operating under the traditional mortgage framework, but newer scoring models are entering the market. Lenders should verify the models accepted by their investor rather than assuming FICO Score 4 will apply to every conforming loan indefinitely.

This article is for informational purposes only and does not constitute legal advice. Consult a qualified attorney regarding your specific compliance obligations.