Mortgage lenders don't just look at your credit score.
They run one number that quietly decides whether you get approved or get shown the door: your debt-to-income ratio, or DTI.
Add up every monthly debt payment you make — car loan, student loans, minimum credit card payments, personal loans.
Then divide that total by your gross monthly income (what you earn before taxes).
If you bring home $6,000 a month and owe $1,500 in debt payments, your DTI is 25%.
Mortgage lenders care because it tells them how much room you have left to absorb a new housing payment.
Most conventional loans top out around 43% DTI, though some programs allow up to 50% with strong credit and reserves.
FHA loans often stretch to 43% to 50% depending on the lender.
Lenders pull your minimum payments, not what you actually pay.
If you owe $8,000 on a card but pay $300 a month to knock it down, the lender still uses the minimum — maybe $160 — in the calculation.
But if you've been paying the minimum on five cards, those small amounts add up fast.
A common mistake is assuming your rent doesn't count.
It doesn't appear in DTI, but your new mortgage payment — principal, interest, taxes, and insurance — absolutely does.
On a $350,000 home with a 7% rate, that's roughly $2,700 a month before you even factor in HOA fees.
Paying down revolving debt is the fastest lever, because killing a card removes its minimum payment entirely.
Paying off a $4,000 balance with a $120 minimum drops your DTI by 2 percentage points if you earn $6,000 a month.
Do that across three cards and you've freed up serious borrowing room.
Boosting income helps too, but lenders want to see it on paper for at least two years if it's variable.
A raise or a side gig that shows up on tax returns counts.
One more thing people miss: co-signing a loan for a family member counts against your DTI even if they pay it.
If you're house hunting in the next year, think twice before helping someone else finance a truck.
Rates are hovering in the mid-6% to low-7% range for a 30-year fixed, which means every dollar of debt matters more than it did when money was cheap.
A DTI that passed easily in 2020 might not clear today.
If you're not sure where you stand, run the math before you talk to a lender.
Add your minimum payments, divide by gross income, and see the number.
If you're over 36%, you've got work to do — and it's better to find out now than after a seller accepts your offer. **The bottom line:** DTI is the quiet gatekeeper of homeownership, and it rewards patience more than it rewards optimism.
Paying down cards and avoiding new debt for six to twelve months can change your approval odds more than any credit score tweak.
Final Thoughts
Know your number before you fall in love with a house.