Debt-to-Income Ratio (DTI)
The debt-to-income ratio compares monthly debt payments to gross income. Understand how lenders use DTI to evaluate mortgage eligibility.
Definition
The debt‑to‑income (DTI) ratio is a key metric lenders use to evaluate a borrower’s ability to repay a mortgage. It compares a borrower’s total monthly debt obligations (such as credit cards, student loans, car loans, and proposed housing expenses) to their gross monthly income. Two ratios are considered: the front‑end DTI, which measures housing costs (mortgage principal and interest, property taxes, homeowners insurance, and HOA fees) relative to income, and the back‑end DTI, which includes all debts. Generally, lenders prefer a back‑end DTI below 43% for qualified mortgages. Maintaining a low DTI improves chances of loan approval and may lead to more favorable interest rates.
Why It Matters
DTI sets your price ceiling more directly than your credit score does. Gross $12,000 a month with a $650 car payment and $300 in student loans, and a 45% back-end limit leaves roughly $4,450 for principal, interest, taxes, insurance and HOA dues combined. Retire that car loan and you can buy roughly $95,000 more house, which is also why lenders beg you not to finance a truck before closing.
Examples
A buyer at 44% DTI leases a new SUV for $700 a month three weeks before closing. The lender re-pulls credit, the ratio hits 50%, and the loan is denied at the table.
A couple's income-driven student loan plan shows a $0 payment. Agency guidelines require using 0.5% of the balance instead, so $340 a month counts against them anyway.
A condo buyer finds the association's $1,100 monthly dues alone push front-end DTI past 33%, because lenders weigh dues the same as taxes and insurance.
Tips
Compute both ratios yourself before applying: housing costs over gross income, then total debts over gross income. If the second exceeds 43%, pay off the balances with the largest monthly payments first, not the highest interest rates.
Open, close or co-sign nothing between preapproval and funding. Credit and employment get re-verified days before closing, and a co-signed loan counts fully against you.
Self-employed borrowers are judged on net income after deductions, averaged over two years. Aggressive Schedule C write-offs cut your tax bill and your borrowing power together.
Related Terms
Qualifying Ratio
Qualifying ratios compare debt to income for mortgage approval. Understand front-end and back-end ra...
Loan-to-Value (LTV) Ratio
The loan-to-value (LTV) ratio compares the loan amount to the property’s value. Learn why LTV matter...
FHA Loan
An FHA loan is a government-backed mortgage with low down payment requirements. Learn eligibility cr...
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