Credit glossary
Mortgage overlay
A lender's own requirement layered on top of a loan program's rules, such as a higher minimum credit score than FHA or Fannie Mae requires.
Agencies like HUD, Fannie Mae and Freddie Mac set program rules, but the lender that underwrites and funds your loan carries its own risk and answers to investors, so it often adds stricter rules. FHA allows maximum financing from a 580 decision score, yet many lenders set a higher floor. Fannie Mae's Desktop Underwriter has no minimum score for newer casefiles, yet lenders may still require 620 or more.
Overlays explain why a no from one lender isn't a no from the program. Ask each lender two questions: what's your minimum for this loan type, and is that the program's rule or yours? Some lenders also refuse manual underwriting, which matters for low-score, no-score or disputed files. Shopping lenders within a 14-day window keeps the extra inquiries from costing more than one.
Guides that go deeper
- Credit score for an FHA loan: the 580 and 500 rules, explainedFHA allows scores down to 500 with 10% down and 580 for 3.5% down, but lenders add overlays. How FHA picks your score and what changes in 2027.
- Credit score for a conventional loan after Fannie Mae dropped 620Fannie Mae's automated underwriting no longer requires a 620 score, but manual loans, lender overlays and pricing still do. What changed and what didn't.
- Getting your credit mortgage-ready in 12 months, month by monthA month-by-month credit plan for the year before a mortgage: what to check, what to fix, what to leave alone, and the timing rules underwriters use.
Sources
- Mortgagee Letter 2026-11: Updated Minimum Decision Credit Score Methodology for the Implementation of Alternative Credit Scores, U.S. Department of Housing and Urban Development
- DU Version 12.0 November 15, 2025 Release Notes, Fannie Mae
- B3-5.1-01, General Requirements for Credit Scores, Fannie Mae Selling Guide
- Letter to FHFA on treatment of credit reporting disputes (November 14, 2014), National Consumer Law Center
- How to Rate Shop and Minimize the Impact to Your FICO Scores, myFICO
This is education, not legal or financial advice. Spot an error? Tell us and we'll fix it.