Your debt to income ratio, or DTI, is one of the most important numbers in the mortgage approval process. Many first time buyers get tripped up here even when their credit score is strong. If your DTI is too high, lenders will deny your application even if you have savings and good credit. Understanding what DTI is, how to calculate it, and how to improve it before applying gives you control over your mortgage approval odds.

What Is Debt to Income Ratio?

Your debt to income ratio is the percentage of your gross monthly income that goes toward monthly debt payments. It is calculated by dividing total monthly debt payments by gross monthly income.

There are two types of DTI. Front end DTI (also called housing ratio) includes only housing costs: mortgage payment, property taxes, insurance, and homeowners association fees. Back end DTI includes all monthly debt payments: the mortgage payment, credit card minimums, car loans, student loans, personal loans, child support, and alimony. Back end DTI is what most lenders focus on because it shows your total financial obligation.

Lenders set maximum DTI limits. Most programs allow back end DTI up to 43 to 50 percent. This means if your gross monthly income is $6,500, you can have monthly debt payments (including your mortgage) of $2,800 to $3,250.

How to Calculate Your DTI: Step by Step Example

Step 1: Calculate Your Gross Monthly Income

Use your gross income before taxes and deductions. If you earn $78,000 per year, your gross monthly income is $6,500. If you have a spouse or co borrower, add their income too. If you are self employed, use your average income from the past two years.

Step 2: List All Monthly Debt Payments

Add up every monthly debt payment:

• Car loan payment: $400
• Student loan payment: $300
• Credit card minimum: $100
• Other debts: $0
• Total current debt: $800 per month

Step 3: Calculate Back End DTI Before Mortgage

Divide total debt by gross monthly income: $800 divided by $6,500 equals 12.3 percent. This is your DTI before taking on a mortgage. This is good.

Step 4: Estimate Your Mortgage Payment

Let us say you want to buy a $350,000 home. FHA with 3.5 percent down means you borrow $337,750. At 7 percent interest over 30 years, your monthly mortgage payment (principal and interest only) is approximately $2,370. Add property taxes, homeowners insurance, and mortgage insurance: roughly $450 combined. Total housing payment: approximately $2,820.

Step 5: Calculate Back End DTI with Mortgage

New total monthly debt: $800 (existing) plus $2,820 (mortgage) equals $3,620. Divided by $6,500 gross income equals 55.7 percent DTI.

The Problem: Most lenders allow maximum 43 to 50 percent DTI. At 55.7 percent, you exceed the limit and will be denied despite good credit and savings. You would need to earn more, pay off debt, or buy a less expensive home.

Reference: CFPB Mortgage Application Guide Section 3.4 (Debt to Income Calculation).

DTI Limits by Loan Type

FHA: Standard limit is 43 percent back end DTI. With compensating factors (strong credit, large reserves, low loan to value), FHA allows up to 50 percent. FHA is the most forgiving program for high DTI.

Conventional: Standard limit is 45 percent. Some lenders go to 50 percent with strong compensating factors. Depends heavily on your credit score and down payment percentage.

VA: Official guideline is 41 percent, but VA evaluates compensating factors and residual income (leftover money after debts). Veterans with excellent credit or high residual income may exceed 41 percent.

USDA: Strict 41 percent maximum. USDA is the least flexible with DTI.

Reference: HUD Mortgagee Letter 2025 03 (FHA), Fannie Mae Selling Guide (Conventional), VA Home Loan Program guidelines, and USDA Single Family Housing Guaranteed Loan Program rules.

What Counts as Debt in Your DTI Calculation

What DOES count:

• Car loans and auto payments
• Student loans (even if deferred or in forbearance, depending on program)
• Credit card minimum payments
• Personal loans
• Medical debt in collection
• Child support and alimony
• Other mortgages or property loans
• Your new proposed mortgage payment

What does NOT count:

• Utilities (electricity, gas, water)
• Homeowners or renters insurance
• Cell phone bills
• Internet or cable subscriptions
• Grocery bills
• Gas for your car
• Medical bills not in collection

The distinction is important. Debt payments that show up on credit reports count. Regular living expenses that do not appear as monthly obligations do not count toward DTI, even though they are real monthly costs.

Reference: Fannie Mae Selling Guide and CFPB Mortgage Disclosure Guide.

Student Loans and DTI: A Major Issue for Utah Buyers

Student loans are the single biggest DTI problem for many first time buyers, especially younger borrowers. The calculation method matters tremendously.

FHA Treatment: If you have an income driven repayment plan (IBR, PAYE, REPAYE, SAVE) showing $0 monthly payment, FHA counts 0.5 percent of the loan balance as your monthly payment. A $40,000 student loan balance counts as a $200 monthly debt payment. This is reasonable.

Conventional Treatment (Fannie Mae): If you have an income driven repayment plan with a $0 payment, Fannie Mae counts 1 percent of the loan balance as your monthly payment. A $40,000 loan counts as a $400 monthly payment. If the actual payment is greater than 1 percent, they use the actual payment. This is more generous than it sounds but harsher than FHA.

The Problem: If you have large student loan balances with $0 payments, the amount lenders impute can kill your DTI. Borrowers with $60,000 to $80,000 in student loans often face this issue.

If this is your situation, ask your lender about getting out of income driven repayment before you apply. If you consolidate federal loans into a standard 10 year repayment plan, your actual payment is much lower than the imputed amount, potentially reducing your DTI significantly.

Reference: HUD Mortgagee Letter 2021 13 (Student Loan DTI Treatment) and Fannie Mae Selling Guide B3.

How to Lower Your DTI Before Applying

Pay Off Smallest Debts First: This is the fastest way to reduce monthly debt payments. If you have a $150 credit card payment and a $100 car payment, paying off the credit card first frees up $150 per month immediately. This is faster than paying off larger balances.

Avoid New Debt: Do not take out car loans, credit cards, personal loans, or other debt in the months before applying. Each new debt increases your monthly obligations and lowers your approval odds.

Increase Income: If possible, increase your income in the months before applying. A second job, side income, or bonus adds to your gross income, improving your DTI ratio. Self employment income must be documented with tax returns.

Pay Down Credit Card Balances: Lenders count the minimum payment, not the balance. If you have a $5,000 credit card balance at a 3 percent minimum, that is a $150 monthly obligation. Paying it down to $1,000 reduces the minimum to $30. This helps DTI significantly.

Refinance Student Loans: Moving from income driven repayment to a standard 10 year plan lowers the imputed payment in most cases. Refinancing federal loans to a private lender reduces the payment as well (but you lose federal protections).

Wait for Income Increase: If you expect a raise or promotion in a few months, waiting might be worth it. A $500 monthly income increase improves your DTI significantly on a large loan.

Reference: CFPB Debt Reduction Strategies and myFICO credit improvement guides.

Compensating Factors: When DTI is Slightly High

If your DTI is slightly above the standard limit, lenders consider compensating factors. These are strengths in your application that offset the high DTI. Common compensating factors include:

• Large cash reserves (savings equal to several months of mortgage payments)
• Low loan to value ratio (high down payment)
• Strong credit score (740 or above)
• Long history of paying a housing payment similar to your new mortgage
• Significant equity in other properties
• Residual income (leftover money after all debts, only VA)

If you are at 48 percent DTI with a 720 credit score and $50,000 in savings, the lender might overlook the DTI because your other strengths show you can manage the mortgage. But compensating factors are discretionary. There is no guarantee.

Reference: HUD Mortgagee Letter guidelines and Fannie Mae Selling Guide compensating factor guidance.

Key Actions to Take Right Now

• 1

  Calculate your current DTI. Add up all monthly debt payments, divide by gross monthly income. If you are above 43 percent, you have work to do.

• 2

  Identify smallest debts to pay off. Look for credit card balances, personal loans, or small car payments you can eliminate in the next few months.

• 3

  Check student loan status. If you have student loans, verify whether you are in income driven repayment. Ask your lender how they will calculate this debt.

• 4

  Review credit cards. List all credit card minimum payments. Pay down the highest balance cards to lowest, starting with the smallest balance to free up payments quickly.

• 5

  Identify income increase opportunity. If possible, increase household income through a part time job or documented bonus in the months before applying.

• 6

  Meet with a lender. Provide your estimated income and debts. Ask them to calculate your maximum affordable home price based on your DTI limit.