DTI Waiver Fannie Mae 2026: When DU Approves Above the 50% Back-End Limit

Fannie Mae's Selling Guide sets a 50% maximum back-end DTI for manually underwritten loans. But Desktop Underwriter can approve files with back-end DTI above 50% when compensating factors are strong enough. These DU Approve/Eligible findings with DTI above 50% are valid -- the lender can sell the loan to Fannie Mae without a DTI waiver request. The key is understanding what DU is weighing to produce that approval.

How DU Evaluates High-DTI Files

DU uses a risk model that weighs multiple factors simultaneously. A file with 52% DTI and a 780 FICO, 20% down, 24 months of reserves, and no layered risk may receive Approve/Eligible. The same file with 52% DTI and a 640 FICO, 3% down, and 2 months of reserves will receive Refer. DU does not apply a hard cap at 50% for AUS approvals; it evaluates the overall risk profile. This is why running DU before concluding a file is ineligible is always the right move.

Compensating Factors That Help High-DTI Files in DU

• ✦High FICO score (720+): significantly improves DU approval probability at elevated DTI
• ✦Low LTV / large down payment: reduces lender risk and improves DU scoring
• ✦Significant liquid reserves: 12+ months of PITIA in verified liquid assets is a strong compensating factor
• ✦Stable long-term employment: same employer 5+ years reduces income risk in the model
• ✦Limited layered risk: a high-DTI file with one risk factor may clear; multiple risk factors stacked together will not

Presenting High-DTI Files Correctly

When DU returns Approve/Eligible with DTI above 50%, document the finding and submit the full DU certificate with the file. Lenders cannot overlay a 50% cap on DU-approved files without disclosing that overlay. If your lender has a 50% DTI overlay and the borrower's DTI is 52%, find a lender without that overlay -- the DU approval is valid and the file is deliverable to Fannie Mae. Overlays are lender-specific, not agency requirements.