Fannie Mae automated underwriting system that assesses a submitted conventional mortgage casefile and issues findings.
Desktop Underwriter, or DU, is Fannie Mae’s automated underwriting system for assessing a submitted mortgage casefile and issuing an underwriting recommendation and findings report.
DU analyzes application and credit data to assess mortgage delinquency risk and whether the loan appears eligible for delivery to Fannie Mae. The lender remains responsible for data accuracy, documentation, compliance, prudent underwriting judgment, and the final approve-or-decline decision.
Borrowers may hear that a file has “DU approval,” but DU does not approve the consumer’s application on the lender’s behalf. A favorable DU recommendation means the casefile appears to satisfy the evaluated credit-risk and eligibility standards based on the submitted data.
The accompanying DU Underwriting Findings report tells the lender what must be verified and which messages apply. A lender cannot rely on the headline recommendation while ignoring contradictory documents, undisclosed debt, inaccurate occupancy, property problems, or its own stricter Investor Overlay.
DU can also affect documentation. Some casefiles receive messages allowing a specific documentation approach, while others require more support. The lender must follow the findings that apply to the final, accurate submission.
DU may be used during conventional preapproval, after a property is selected, during formal underwriting, and after material changes. The lender submits data from the application, credit report, proposed mortgage, and property scenario.
The underwriter then reconciles the output with the file. If the loan or borrower information no longer matches the last submission, the lender generally updates and resubmits the casefile, subject to the applicable DU tolerances and rules.
| DU recommendation | Plain-language interpretation |
|---|---|
| Approve/Eligible | Favorable credit-risk assessment and eligible for the submitted Fannie Mae path, if all findings are satisfied |
| Approve/Ineligible | Favorable credit-risk assessment, but at least one eligibility issue prevents delivery as submitted |
| Refer with Caution | The casefile does not meet DU credit-risk standards for delivery as a DU loan |
| Out of Scope | DU cannot evaluate the casefile under the ordinary recommendation framework |
The exact recommendation and messages on the current findings report control. A shortened phrase from a loan officer is not a substitute for the lender’s review of that report.
A borrower seeks a conventional purchase mortgage. The lender submits the casefile to DU and receives Approve/Eligible with findings requiring income, asset, credit, and property documentation.
The appraisal later supports a lower value, increasing the loan-to-value ratio. The lender updates DU. If the revised file still receives an eligible recommendation and satisfies the new findings, underwriting can continue. If it becomes ineligible, the lender must change the structure or use another valid path.
An automated underwriting system is the broad software category. DU is Fannie Mae’s specific AUS.
Loan Product Advisor is Freddie Mac’s system. LPA uses Accept or Caution as risk classes and reports purchase eligibility separately; those labels should not be described as DU recommendations.
Approve/Eligible is one DU recommendation. DU is the system that generates the recommendation and the full findings report.
AUS findings are the complete output. They include more than the recommendation, such as verification messages, conditions, and eligibility information.
Conditional approval is issued by the lender after underwriting review. It can rely on DU output but is not issued by DU.