What Is Debt-to-Income Ratio?

The Espresso ShotEverything all at once. Short and strong.

  • DTI is your monthly debt payments, including the new house payment, divided by your income before taxes.
  • Car, student loan, and credit card payments count. Groceries, utilities, and your phone bill don’t.
  • There’s no single cutoff. Each loan type sets its own limit, so ask your lender which one they use.

Debt-to-income ratio sounds like something that needs a calculator and a headache. It’s actually one simple idea, and once you see it, a lot of what lenders say starts to make sense.

In plain terms, it’s the share of your monthly income that’s already spoken for by debt payments, including the new house payment you’re asking for. Lenders usually call it DTI.

How it’s figured. A lender adds up your monthly debt payments, divides that by your income before taxes, and looks at the percentage. They’re really asking one question: after your other bills, is there room for a house payment?

What counts, and what doesn’t. Car payments, student loans, credit card minimums, and personal loans all count. So does the new mortgage payment, all of it: principal, interest, property taxes, and homeowners insurance. Groceries, utilities, your phone bill, and subscriptions matter for your budget, but they’re not on the lender’s list.

Let me walk you through the math. A typical house in Buckley or Enumclaw runs somewhere around $650,000, so that’s the one we’ll look at. Put 5% down on a 30-year loan at a rate around 7.3%, and your monthly payment comes to roughly $5,300. Here’s where that goes:

  • About $4,230 for principal and interest
  • About $490 for property taxes
  • About $150 for homeowners insurance
  • About $390 for mortgage insurance, since the down payment is under 20%

Now picture a household earning $15,000 a month before taxes, with a $450 car payment, $300 in student loans, and $100 in credit card minimums. That’s $850 in other debt. Add it all up: $5,300 plus $850 is $6,150, and $6,150 divided by $15,000 is about 41%.

Is 41% okay? For most loans, yes, but there’s no single cutoff; each loan type sets its own. Fannie Mae’s guidelines, which many conventional loans follow, start at 36% and allow up to 45% for a loan reviewed by hand, or up to 50% through its automated approval. FHA loans typically start at 43% and can go higher with strengths like savings or strong credit. So 41% fits, often with room to spare. These limits change, so ask what your lender uses.

Front-end and back-end. You may hear both. Front-end is the housing payment on its own: $5,300 out of $15,000, or about 35%. Back-end is everything together, the 41% we just figured. When someone says DTI, they almost always mean back-end.

What you can do before you talk to anyone. Paying down a credit card usually shrinks its minimum payment, and that minimum counts. Pay off the car loan and the credit card, and the same house drops to about 37%. It’s also one more reason to hold off on new loans while you’re getting ready. And write down every monthly payment you have, so you know your own number before a lender tells you.

What to ask your lender. “For the loan I’m looking at, what debt-to-income limit do you use, and which of my debts are you counting?” Different loan types draw the line in different places, and a good lender will happily explain where theirs is.

Prices and rates move, so treat these numbers as an example, not a quote. I can show you how the math works; your lender is the one who can tell you how it works out for you.