Mortgage rates have cooled from their post-2022 peaks, and more buyers are jumping back into the market.
But a surprising number of them are getting turned down for a reason that has nothing to do with their credit score: their debt-to-income ratio, or DTI.
Lenders add up your minimum monthly debt payments — car loans, student loans, credit card minimums, personal loans — and divide that total by your gross monthly income.
If you bring in $6,000 a month and owe $300 on a car and $200 in card minimums, your DTI is about 8%.
The trouble starts when you add a mortgage payment into the mix.
Most conventional loans cap your total DTI at 43%, and many lenders prefer 36% or lower.
On that same $6,000 income, a $1,800 housing payment plus $500 in existing debts puts you at 38% — tight, but workable.
Add a $400 truck payment and you're suddenly in the danger zone.
What trips people up is that federal rules treat your entire student loan balance differently than you might expect.
Even if you're on an income-driven repayment plan paying $0, many lenders still count a percentage of the total loan balance against you.
A $40,000 student loan can quietly add hundreds to your calculated monthly obligations.
FHA loans are more forgiving, sometimes allowing DTIs up to 50% with compensating factors like cash reserves or a long employment history.
But that flexibility comes with mortgage insurance premiums that add to your monthly cost.
There's no free lunch — a higher DTI allowance usually means paying more somewhere else.
If your ratio is the holdup, a few moves can help.
Paying down a credit card balance lowers the minimum payment, which lowers your DTI immediately — often faster than saving a bigger down payment.
Avoid financing a car or furniture in the six months before you apply.
And if you're close to the line, ask about paying down student loans or getting a co-borrower whose income counts.
One number worth knowing: roughly one in four mortgage applications that get denied cite debt-to-income as a factor, according to federal housing data.
It's one of the most common — and most fixable — obstacles in the process.
Before you tour a single open house, run your own numbers.
Add up your minimum payments, divide by your income, and see where you land.
Fixing a DTI problem takes months, not days, so starting early beats scrambling after you've fallen for a house.
Final Thoughts
A little math now can save you a rejected offer later.