DTI (Debt-to-Income Ratio)
The percentage of your gross monthly income that goes toward debt payments. Front-end DTI covers housing costs only (PITI); back-end DTI includes all recurring debts. The traditional benchmark is the 28/36 rule: no more than 28% on housing, 36% total. Conventional lenders typically allow up to 43–45% back-end DTI with compensating factors.
How it works in practice
How much DTI a program tolerates varies more than most borrowers expect. Conventional loans underwritten through the automated systems routinely approve back-end ratios up to 45% — and to 50% with strong compensating factors like reserves and credit. FHA can stretch further, sometimes into the mid-50s with an automated approval. Non-QM programs commonly cap between 43% and 55% depending on documentation type. The old 28/36 rule survives as a budgeting sanity check, not a lending limit.
For self-employed borrowers, the numerator is straightforward — housing payment plus the debts on your credit report — but the denominator is where files are won or lost. Your income isn't what you invoice; it's the qualifying figure a lender computes: a two-year average of net self-employment income on a conventional loan, or deposits after an expense factor on a bank statement program. A borrower with heavy write-offs can show a 60% DTI on paper while their cash flow sits closer to 30% — same person, different denominator.
Three levers move DTI fastest. Paying off a car loan or credit card removes its entire monthly payment from the calculation, often outperforming a bigger down payment dollar-for-dollar. Choosing the documentation path that reads your income most favorably raises the denominator. And buying below your maximum approval keeps the housing payment — the largest single line — in check.
Common questions
Do lenders count taxes and insurance in DTI?
Yes. The housing figure is the full PITI — principal, interest, property taxes, homeowners insurance, plus HOA dues and mortgage insurance where they apply. A low rate doesn't guarantee a low ratio if taxes and insurance are heavy in your market.
Is there a DTI that guarantees approval?
No single number does. Under roughly 36% almost every program is comfortable; between 36% and 50% approval depends on the rest of the file — credit, reserves, down payment; above 50% the options narrow to FHA with strong factors and certain non-QM programs.
Related terms
- Qualifying income — The income figure a lender actually uses when calculating your DTI — not your gross revenue, not your total de…
- Schedule C — The IRS form where sole proprietors and single-member LLCs report business income and expenses. Conventional l…
- Net income — Income after all business deductions. On a tax return, this is Schedule C net profit. It’s the number conventi…
- Form 1084 — Fannie Mae’s self-employed income analysis worksheet. Lenders use it to standardize how they calculate qualify…
- 2-year average — How conventional lenders handle self-employed income variability: they average qualifying income across the tw…
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Sources
Educational definition only — not financial, legal, or tax advice. Programs and limits change; verify current terms with a licensed professional.