Mortgage Navigator • Conventional • Agency Comparison

Fannie Mae vs. Freddie Mac: same market, different rulebooks.

Most borrowers do not need to memorize the agencies. Their loan officer does need to know when moving a file from one agency to the other can change the answer.

TopicFannie MaeFreddie MacWhy it matters
Automated underwritingDesktop Underwriter (DU)Loan Product Advisor (LPA)Different risk models can produce different results on the same borrower.
AUS minimum credit scoreNo minimum credit score required for DU loan casefiles.No minimum Indicator Score required for LPA Accept mortgages.A borrower below the old 620 shorthand may still receive an eligible AUS result.
Affordable productHomeReadyHome PossibleBoth target qualifying lower-income borrowers, but execution details differ.
Standard 3% down pathStandard 97% LTV option subject to eligibility.HomeOne is Freddie's first-time-buyer 3% down path outside Home Possible.First-time status and product selection can matter.
Guide authorityFannie Mae Selling GuideFreddie Mac Single-Family Seller/Servicer GuideDo not assume a Fannie rule automatically applies to Freddie.

The MortgageDadOf3 approach

We will not create duplicate Fannie and Freddie articles when the answer is effectively the same. Each conventional article will instead include a clearly marked agency comparison when the difference could change qualification, documentation or the transaction.

Question we will ask throughout this library: “If this does not work under one agency, could the other agency solve it?”
Still not a guarantee: an AUS approval is only one part of eligibility. The loan must also satisfy the agency guide, product terms, property requirements, mortgage insurance when applicable and the lender's own overlays.

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.