It's not your credit score, and it's not your down payment.
It's your debt-to-income ratio, or DTI, and in 2024 and 2025 it has quietly become the gatekeeper that decides whether you buy a house or keep renting from a landlord who raises the rent every spring.
Add up every monthly debt payment — car loan, student loans, minimum credit card payments, personal loans.
Divide that by your gross monthly income before taxes.
If you earn $6,000 a month and owe $2,400 in payments, your DTI is 40%.
Conventional lenders generally prefer 36% or lower.
Many will stretch to 43%, and some government-backed loans push past that.
Above those lines, you're not rejected outright — you're just quoted a worse rate, or told to bring more cash.
Home prices climbed hard through 2021 and 2022 and never fully came back down.
Meanwhile the average 30-year fixed mortgage rate has bounced between roughly 6% and 8% since 2022, compared with the sub-3% era that spoiled a generation of buyers.
At 3%, a $400,000 loan costs about $1,686 a month in principal and interest.
Nearly a thousand dollars more every month — and that payment eats DTI from the front.
Then there's the other half of the fraction: income.
Wages have risen, but groceries, insurance, and childcare ate most of the gain.
Credit card balances hit record highs, and the average annual percentage rate on those cards has hovered near 20% or higher.
Every dollar of revolving debt you carry raises your minimum payment, and your minimum payment raises your DTI.
This is where the incentives get interesting.
The 43% threshold isn't a law — it's a guideline from the Consumer Financial Protection Bureau's qualified mortgage rules, and lenders lean on it because it protects them, not you.
A high-DTI borrower is more likely to struggle, and a struggling borrower is a foreclosure risk.
So the industry built a system that filters people out earlier rather than pricing them honestly.
If you're at 44%, you're not told "this will cost you more." You're told "come back with a bigger down payment." There's a workaround, and it's the one nobody advertises: paying down debt right before you apply.
Paying off a $300 monthly car loan can drop your DTI by five percentage points, which can be the difference between a 6.5% offer and a 7.4% offer over 30 years.
Lenders will happily let you carry the debt as long as you qualify.
Nobody at the closing table is paid to tell you the ratio is negotiable.
So do the arithmetic yourself before a loan officer does it for you.
Pull your three credit reports, add up every minimum payment, and divide by your real gross income — not your take-home.
If the number scares you, the debt is the problem and the mortgage rate is just the messenger.
The blunt truth is that DTI is less a measure of your worth than a measure of how much risk the lender can push onto you.
It's a useful discipline for your own budget, but it's not a moral verdict, and it's not fixed.
Final Thoughts
The people profiting from the current system have no incentive to explain that to you.