What Is Debt-to-Income Ratio (and Why It Decides Your Mortgage)

If you have ever asked "why can't I qualify?", the answer usually starts with two letters: DTI. Debt-to-income ratio is the share of your gross monthly income that already goes to debt payments — and the share a new mortgage payment would add.

The two numbers that matter

Lenders look at two ratios:

• Front-end ratio — just the housing payment (principal, interest, property taxes, insurance, HOA dues, and mortgage insurance) divided by your gross monthly income.
• Back-end ratio — the housing payment plus every other monthly debt payment: car loans, student loans, credit card minimums, child support or alimony you pay.

Most loan programs care most about the back-end number. It is the one that tells an underwriter whether the full picture fits.

What counts as "debt"

More than most people expect:

• Minimum credit card payments (not your balance — the minimum)
• Student loan payments, even when deferred in some cases
• Car loans and leases
• Personal loans and "buy now, pay later" plans with a remaining balance
• Cosigned loans, even if someone else actually pays them
• Child support and alimony you pay

What usually does not count: your rent (for a purchase), utilities, phone bills, insurance premiums you pay directly, and everyday spending.

Where the lines usually sit

There is no single bright line — each program, lender, and file differs — but as a rough educational guide, many conventional loans look for a back-end DTI in the mid-40s or below. FHA financing can stretch higher in some files. Government-guaranteed programs like NACA or Section 184 evaluate your whole profile and can work with different numbers.

How to move your DTI in weeks

1. Pay down a card's minimum. Minimums are recalculated from the balance — paying a card down shrinks the payment lenders count.
2. Close nothing. Closing a card does not remove the counted payment on loans you still owe.
3. Pay off small installment loans completely. A paid-off loan with three payments left can sometimes be excluded with a $0 balance letter.
4. Check cosigned loans. Twelve months of someone else's on-time payments (bank statements) can knock a cosigned debt out of your ratio.
5. Watch new debt. A new car payment right before you shop for a house can move your budget by tens of thousands of dollars in price.

See your own number

Our free readiness check walks through your income, debts, and credit band and shows an estimated DTI with an honest list of what could start the process. It takes about seven short steps and never pulls your credit.

Run the free check →