Housing · Debt
Google “how much house can I afford” and you get a payment. Lenders do not buy a payment. They buy a ratio of monthly debts to gross income. That ratio is DTI, and it is why two households with the same salary get different loan sizes.
Updated 2026-09-08 · 9 min read · Educational, not a pre-approval. Run the DTI calculator with your numbers.
Front-end (housing) DTI is PITI — principal, interest, taxes, insurance — plus HOA and mortgage insurance, divided by gross monthly income. Back-end (total) DTI is housing plus every other monthly debt the credit report and application show. Back-end is the one that kills files.
Front-end
The payment you will make on this house. Conventional target: 28%.
Back-end
Housing plus cars, cards, students, support. Conventional target: 36%.
Automated underwriting can stretch these. Compensating factors (reserves, credit score, leftover income) matter. Plan to the published ceilings anyway — stretching DTI is how a rate lock turns into mortgage insurance, a price adjustment, or a denial two days before closing.
| Program | Front-end | Back-end | Notes |
|---|---|---|---|
| Conventional (Fannie/Freddie) | ~28% | ~36% | Desktop Underwriter / Loan Product Advisor may go higher with score + reserves. |
| FHA | ~31% | ~43% | Can stretch with compensating factors; mortgage insurance is not optional. |
| VA | — | ~41% guideline | Residual income (cash leftover after debts) often matters more than the ratio. |
| USDA | ~29% | ~41% | Income limits and rural-area maps apply on top of DTI. |
Related: how much house · HELOC vs cash-out · how much rent · PMI.
Pretax 401(k) and HSA do not sit in the numerator, but they shrink take-home. That is why a household can “qualify” on paper and still fail a real budget. Pair this page with the 2026 paycheck estimator before you shop.
If you are on income-driven repayment and the billed payment is $0, many conventional files recast the debt as 0.5% of the outstanding balance per month. A $60,000 balance becomes a $300 DTI line you did not budget. FHA and VA are more likely to use the documented IDR payment. Ask the loan officer which rule they will run before you spend money on an appraisal. Payment vs recast vs RAP/IBR: IDR vs refinance calculator — this page will not duplicate that math.
Paying a card from $4,000 to $1,000 barely moves DTI. The underwriter uses the minimum payment, which barely fell. Paying the card to $0 so the payment disappears does. Same with a car: extra principal is for interest math; payoff is for DTI math. See snowball vs avalanche for which debt to kill first when the goal is a mortgage, not lifetime interest.
The other lever is income: a documented raise, a second borrower, or a side gig with two years of returns. Authorized-user tradelines can help credit score. They do not add the other person’s income to your DTI.
36% of gross on a $90,000 salary is $2,700 a month in debts. After tax, that can be half of take-home. A lender who says yes is not saying you will like the life. Size the house with leftover money after a 3–6 month emergency fund and the 401(k) match — then see if DTI still clears. The PayPal playbook is the 90-day sequence if you are close and the file is not.
Free tool
Front-end, back-end, leftover payment room, shareable URL.
PayPal
Which payment to kill, what to document, when to wait.
Not a loan offer. Program overlays change. Confirm with a licensed loan officer. Premium restore: /account.