The full explanation
Lenders use it to measure whether you can manage the payment; each loan type and lender sets its own limit, and assistance programs usually publish theirs. Paying down debt before applying improves your DTI.
An example
The bank tells Nora her DTI is high because of the car loan. If she pays it off before applying for the mortgage, her DTI drops and the lender sees more room in her budget for a house payment.
With real numbers
Computed with official data for the whole U.S. In your county the numbers may differ.
- Typical income per month
- $6,728
- Home payment, without insurance
- $2,063
- Share of your income
- 31%
If your household earns the typical U.S. income ($6,728 a month before taxes) and buys a $332,700 home with 20% down at the average rate of November 5, 2026, principal, interest and property tax would come to about $2,063 a month. That alone is 31% of your income, before the car, the cards and other debts.
Computed with: American Community Survey (ACS) 5-year estimates (2020–2024) · Freddie Mac Primary Mortgage Market Survey (PMMS) (November 5, 2026) · Fannie Mae Selling Guide B7-1-01 — Provision of Mortgage Insurance (October 17, 2026)
You will see it in…
- The mortgage application and the approval letter
- Assistance program requirements (“maximum DTI”)
- Our calculators, under “How does it compare with income?”
