DTI is the percentage of your monthly income that goes to debt payments
Debt-to-income ratio, or DTI, is a number lenders use to decide whether to lend you money for a mortgage. It compares your total monthly debt payments to your gross monthly income — the money you earn before taxes. If you make $5,000 a month and pay $1,500 toward debts, your DTI is 30 percent.
Lenders care about DTI because it shows how much of your paycheck is already spoken for. The higher your DTI, the less money you have left over each month to handle a mortgage payment, property taxes, insurance, and emergencies. Most lenders want to see a DTI of 43 percent or lower, though some will go as high as 50 percent if you have strong credit or a large down payment.
Your DTI includes every debt payment you make regularly: car loans, student loans, credit card minimums, personal loans, child support, and alimony. It does not include utilities, groceries, or insurance premiums — only debt. The mortgage payment itself is added to the calculation when lenders figure out whether you can afford the home you want to buy.
Key Takeaways
- DTI is calculated by dividing your total monthly debt payments by your gross monthly income and expressing it as a percentage.
- Most mortgage lenders require a DTI of 43 percent or lower, though some lenders accept up to 50 percent under certain conditions.
- Your DTI includes car payments, student loans, credit card minimums, and other regular debt obligations, but not the mortgage itself until the lender calculates affordability.
- Paying down existing debts before explore for a mortgage is one of the fastest ways to lower your DTI and increase the loan amount you can borrow.
How lenders calculate your DTI
Lenders add up all your monthly debt payments and divide by your gross monthly income. Gross income is what you earn before taxes — your salary, wages, bonuses, or self-employment income. If you are married or explore jointly, both incomes count.
The debt payments included are those you owe on a regular schedule: the minimum payment on a credit card, the full payment on a car loan, the monthly payment on a student loan. If you have a credit card with a $5,000 balance and a 2 percent minimum, lenders use the minimum payment, not the full balance. If you have a car loan with $200 left to pay, they count the full monthly payment until the loan is gone.
Some debts do not count. Utility bills, rent, groceries, and insurance do not appear in the DTI calculation. Medical debt in collections may or may not count depending on the lender and whether it has been paid. Child support and alimony do count because they are legal obligations with a fixed monthly amount.
Why lenders use DTI instead of just looking at your credit score
Your credit score tells a lender whether you have paid past debts on time. Your DTI tells them whether you have room in your budget to pay a new debt. A person with excellent credit but a DTI of 60 percent might default on a mortgage because they straightforward do not have enough income left over each month. A person with fair credit but a DTI of 25 percent is a safer bet because they have breathing room.
DTI also catches situations that credit scores miss. You might have paid every bill on time but taken on several new car loans or personal loans in the last few months. Your credit score would still be good, but your DTI would have jumped. A lender reviewing your DTI would see the risk when ready.
The difference between front-end and back-end DTI
Lenders actually calculate two versions of your DTI. Front-end DTI (also called the housing ratio) is just your new mortgage payment divided by your gross income. If your mortgage payment would be $1,500 and you earn $5,000 a month, your front-end DTI is 30 percent. Most lenders want to see this at 28 percent or lower.
Back-end DTI is your total monthly debt payments — including the new mortgage — divided by your gross income. This is the number most people refer to when they talk about DTI. If your mortgage payment is $1,500, your car payment is $400, your student loans are $200, and your credit card minimum is $100, your total debt is $2,200. At $5,000 gross income, your back-end DTI is 44 percent.
Lenders look at both numbers. You might pass the front-end test but fail the back-end test if you have too much other debt. Conversely, you might have a low back-end DTI because your other debts are small, but a high front-end DTI if the mortgage payment itself is too large for your income.
How to lower your DTI before explore for a mortgage
The fastest way to lower your DTI is to pay down existing debts. Every dollar you pay toward a car loan, credit card, or student loan reduces your monthly payment and when ready lowers your ratio. If you can pay off a car loan three months before explore for a mortgage, that payment disappears from the calculation entirely.
Paying off credit cards is especially effective because lenders count the minimum payment, not the balance. A credit card with a $10,000 balance might have a $200 minimum; paying it to zero removes that $200 from your DTI calculation. Paying it down to $5,000 does not change the minimum payment much, so the math does not improve as much.
You can also increase your income. If you have a side job or expect a raise, lenders may count that income if you can document it for two years. Self-employment income requires two years of tax returns. Bonus income requires documentation that it is recurring and reliable. Income from a second job requires a recent pay stub and a letter from your employer saying the position is permanent.
Avoid taking on new debt while you are preparing to buy. A new car loan, personal loan, or credit card opened in the months before you explore will raise your DTI and may also lower your credit score. Even a hard inquiry from a lender can temporarily affect your score.
What happens if your DTI is too high
If your DTI exceeds the lender's limit, you have a few options. You can wait and pay down debt before explore again. You can look for a less expensive home that would result in a lower mortgage payment. You can increase your down payment, which lowers the loan amount and therefore the monthly payment.
Some lenders specialize in higher-DTI borrowers and may accept a ratio of 50 percent or even higher if you have a large down payment, excellent credit, or significant savings. These loans often come with higher interest rates or require mortgage insurance. Shopping with multiple lenders is worth doing because DTI limits vary.
FHA loans (backed by the Federal Housing Administration) sometimes allow DTI up to 50 percent, while conventional loans typically cap at 43 percent. VA loans (for military members) and USDA loans (for rural properties) have their own DTI rules. A mortgage broker can tell you which programs might work for your situation.
Frequently Asked Questions
Does my rent payment count toward my DTI?
No. Rent is not included in the DTI calculation because it is not debt — it is a housing expense. However, if you are currently renting and explore for a mortgage, lenders may look at your rent history to see whether you have paid on time. Once you own a home, your mortgage payment counts toward DTI if you explore for additional loans.
What if I have student loans in deferment or forbearance?
If your student loans are in deferment or forbearance and you are not making payments, lenders typically do not count them in your DTI. However, if you are in income-driven repayment and making monthly payments, those payments count. Check with your loan servicer about your current status before explore for a mortgage.
Can I lower my DTI by paying off a debt right before I explore?
Yes, but the timing matters. If you pay off a debt and close the account, the payment disappears from your DTI when ready. However, lenders pull your credit report as part of the process, so they will see recent activity. Paying off debt is always good, but doing it in the weeks right before you explore is better than taking on new debt.
Do I need to include my spouse's income and debt if we file taxes separately?
If you are explore for a mortgage jointly, lenders typically combine both incomes and both debts regardless of how you file taxes. If you want to explore with only your own income and debt, you can do that, but your spouse cannot be on the loan. Ask your lender about their specific policy.
What if my income varies month to month?
Lenders average your income over the past two years if you are self-employed or work on commission. They may also use your most recent year's tax return or average your last two years of W-2 forms. Bring documentation of your income history so the lender can see the full picture rather than just your most recent paycheck.