Mortgage Navigator • Conventional • AUS

DU vs. LPA: two automated underwriting systems, not two versions of the same calculator.

Fannie Mae's Desktop Underwriter and Freddie Mac's Loan Product Advisor each perform automated credit-risk and eligibility analysis, but they use separate agency models and rules.

Build My Mortgage Game Plan Conventional Navigator

What DU does

Desktop Underwriter analyzes the loan under Fannie Mae's eligibility and credit-risk framework and returns recommendations/messages that guide the lender's underwriting and documentation.

What LPA does

Loan Product Advisor analyzes the mortgage under Freddie Mac's framework and returns a Risk Class and feedback messages governing the applicable Freddie execution.

Agency Difference: the systems are not interchangeable. A borrower can receive an eligible result from one and not the other because the risk models, guide provisions and product rules are not identical.

Credit score change

Fannie removed the minimum third-party credit-score requirement for new DU casefiles beginning in November 2025. Freddie's current Guide likewise states that no minimum Indicator Score is required for an LPA mortgage receiving an Accept Risk Class.

Practical lesson: when a conventional file is close or has an unusual risk factor, “DU said no” should not automatically become “conventional said no.” A legitimate Freddie execution may deserve analysis—and the reverse is also true.

Official sources

Fannie Mae Selling Guide · Freddie Mac Seller/Servicer Guide · FHFA Conforming Loan Limits

Agency guides control over summaries. Lender and mortgage-insurer overlays can be more restrictive.