Debt-to-income explained (front-end vs back-end, what counts, target ranges)
DTI is your monthly debts divided by your gross monthly income. Lenders look at two numbers—front-end (housing only) and back-end (housing + all debts). Here’s how each is calculated, what counts, and common caps by program.
DTI basics & formulas
Gross monthly income is your pre-tax income used for qualifying (hourly × hours, salary/12, averaged variable income, etc.).
- Front-end DTI (housing ratio) =
PITIA÷ gross monthly income. - Back-end DTI (total) =
PITIA + other monthly debts÷ gross monthly income.
PITIA = Principal + Interest + Taxes + Insurance + Association dues (HOA/condo), plus mortgage insurance (PMI/MIP) when applicable.
What debts count (and don’t)
Included in DTI
- Proposed PITIA for the new home (incl. PMI/HOA)
- Revolving cards (minimum payments shown on credit report)
- Installment loans (auto, personal, BNPL if reporting)
- Student loans (see edge cases below)
- Child support/alimony (court-ordered)
- Other mortgages / HELOC draws with payments
Not in DTI
- Utilities, phone, internet, subscriptions
- Groceries, gas, discretionary spend
- Tuition/daycare (unless a reported loan)
- Insurance policies not on the property (auto, health)
If a debt will be paid off prior to closing and the payoff is documented, some programs allow it to be excluded—confirm with your lender.
Typical caps by loan type
| Loan type | Front-end | Back-end | Notes |
|---|---|---|---|
| Conventional | — | ~45% (up to ~50% with strong factors) | Automated findings drive the final cap. |
| FHA | ~31% | ~43% (higher with compensating factors) | PMI (MIP) included in housing. |
| VA | — | ~41% guideline | Residual income test can allow higher. |
| USDA | ~29% | ~41% | Lower with manual underwrite; eligibility rules apply. |
| Jumbo | — | ~38–45%+ | Investor-specific; reserves often required. |
These are common guideposts, not guarantees. Lender overlays and automated underwriting results vary.
Examples & quick math
Example 1: Housing ratio
Gross income: $7,500/mo.
Proposed PITIA (incl. PMI/HOA): $2,250.
Front-end DTI = $2,250 ÷ $7,500 = 30%
Example 2: Total DTI
Other debts: cards $75 + auto $425 + student loan $150 = $650.
Back-end DTI = ($2,250 + $650) ÷ $7,500 = 38.7%
Use the Payment Calculator to tweak rate/points, taxes, or HOA and see DTI shift instantly.
Ways to improve DTI fast
Lower the numerator
- Choose a slightly lower price or larger down payment
- Buy points to reduce the interest rate (check breakeven)
- Pay down revolving balances (utilization) to drop minimums
- Refi/consolidate small loans (only if it reduces payment and timing makes sense)
Raise the denominator
- Add verifiable income (part-time/bonus with sufficient history)
- Add a co-borrower (their debts count too—model both ways)
Edge cases (student loans, self-employed)
Student loans
- If a payment reports on your credit file, lenders usually use that amount.
- If no payment is reporting, some programs apply a percentage of the balance (varies) or accept documentation of an actual payment under an approved plan.
- Deferment/forbearance rules differ—ask your lender how they’ll calculate the payment.
Self-employed / variable income
- Income is typically averaged (e.g., 24 months) and adjusted for write-offs.
- Provide full tax returns; be ready with year-to-date P&L and balance sheet if requested.
- Large swings year-over-year may reduce qualifying income.
Policies vary by loan type and investor. Confirm specifics with your loan officer before restructuring debts.
Next steps
- Run your numbers in the Home Affordability Calculator and set a target price range.
- Use the Mortgage Payment Calculator to test rate, HOA, and PMI scenarios.
- Download the pre-approval docs checklist (PDF) and prep your file.
Disclaimer: Educational info, not financial advice. DTI caps and calculations vary by lender, program, and state.