Credit score gets all the attention. Debt-to-income ratio usually decides how much house you can actually buy.
It is the most consequential number in your file and the one buyers understand least.
The calculation
Your DTI is your total monthly debt payments divided by your gross monthly income, before taxes.
Lenders look at two versions.
The front-end ratio counts only your housing payment: principal, interest, property taxes, homeowners insurance, mortgage insurance if applicable, and HOA dues.
The back-end ratio adds everything else you owe monthly. This is the one that usually decides your file.
What counts
Anything appearing on your credit report as a monthly obligation. Car loans and leases, student loans, credit card minimums, personal loans, and other mortgages.
Court-ordered obligations like child support or alimony count as well.
Student loans get special handling. Even loans in deferment or forbearance typically count, with the payment calculated using a formula when no actual payment is being made. Borrowers on income-driven plans should ask specifically how their loan will be treated, because the answer varies by program.
What does not count
Utilities, phone bills, insurance premiums other than those in your housing payment, groceries, childcare, and streaming subscriptions.
This is worth understanding, because it means the calculation does not reflect your actual monthly budget. A family paying substantial childcare is measured the same as one paying none.
Which brings up the point buyers should sit with: qualifying is not the same as affording. The lender’s ratio ignores real expenses in your life. You should not.
Limits
There is no single universal ceiling. Limits vary by loan program, by lender, and by the strength of the rest of your file.
Compensating factors create flexibility. Significant reserves after closing, a high credit score, a large down payment, or a long history of paying a similar or higher housing cost can all support a higher ratio than would otherwise be allowed.
This is another place where shopping across lenders matters, because guidelines are not uniform.
Why a car payment costs more than you think
Take a hypothetical buyer with a $600 monthly car payment.
That $600 does not just reduce their budget by $600. It occupies room in the back-end ratio, and every dollar of that room could otherwise have gone toward a housing payment.
Depending on the file, eliminating a car payment can increase purchasing power by considerably more than the payment itself. This is why we ask buyers to pause on new vehicles when a purchase is coming.
Four ways to lower your ratio
Pay off small balances entirely. Not paying down, paying off. A card with a small balance and a minimum payment still counts that full minimum against you. Eliminating the account eliminates the payment.
Target installment loans that are nearly finished. Some programs allow excluding a loan with only a few payments remaining. Ask before paying anything down.
Do not take on new debt. Obvious, routinely ignored. No cars, no furniture financing, no store cards.
Document income you are not counting. Part-time work, a side business with a two-year history, or variable income you assumed would not qualify. Sometimes there is income sitting on the table.
Run yours before you shop
Knowing your DTI tells you your real price range, and it tells you which debt to attack first if you want to raise it.
Send us your numbers and we will calculate it with you.
Trinity Lending Company | NMLS #2762052 | Equal Housing Opportunity