The bank didn't care that Jordan had never missed a payment. Didn't care about the 740 credit score. Didn't care that he'd been at the same job for six years. What the bank cared about was a percentage: 47.2%.
That was Jordan's debt-to-income ratio. His monthly debt payments ($3,068) divided by his gross monthly income ($6,500). The conventional mortgage he wanted needed a DTI under 45%. He was $143 a month over the line.
Jordan didn't have a spending problem. He had a $550 car payment, $250 in student loans, $125 in credit card minimums, and was trying to add a $2,143 mortgage (principal, interest, taxes, and insurance). Reasonable numbers, every one of them. But stack them up and the lender said no.
DTI is the financial ratio that sits at the intersection of everything: your income, your debts, your rent or mortgage, and every monthly obligation you've ever signed up for. It's the number that decides whether you can borrow more, and how much.
The 30-second version: Debt-to-income ratio is your total monthly debt payments divided by your gross monthly income. Lenders use it alongside your credit score to decide if you can afford a loan. The "ideal" is 36% or below, but many mortgages approve up to 43-50%. The average purchase mortgage DTI is currently 38.5%. To improve yours, pay down debt or increase income.
How to Calculate Your DTI
The formula is simple. The details trip people up.
DTI = Total Monthly Debt Payments ÷ Gross Monthly Income × 100
Gross monthly income is your pre-tax earnings [1]. Not your take-home pay. Not what hits your checking account. The bigger number on your pay stub. If you earn $78,000 per year, your gross monthly income is $6,500.
Monthly debt payments include:
- Mortgage or rent (for housing DTI, which we'll cover below)
- Auto loan payment
- Student loan minimum payment
- Credit card minimum payments
- Personal loan payments
- Child support or alimony
- Any other recurring debt obligation reported on your credit report
What's NOT included:
- Utilities (electric, water, internet, phone)
- Insurance premiums (unless bundled into your mortgage escrow)
- Groceries, subscriptions, gym memberships
- Taxes you pay (your gross income is pre-tax)
This is the part that confuses people: DTI counts only the minimum required payments on your credit report, not what you actually pay. If your credit card's minimum is $25 but you pay $500 a month, the lender uses $25 [2]. Sounds like it should help you, and it does.
But the reverse catches borrowers off guard. If your student loans are in deferment and your credit report shows a $0 payment, many lenders impute a payment anyway, usually 0.5% to 1% of the total balance [3]. A $40,000 student loan with a $0 payment might still count as $200-$400 per month against your DTI. This is one of the most common mortgage application surprises.
Front-End vs. Back-End DTI
Lenders look at two versions of DTI:
Front-end ratio (housing ratio): Your housing costs (principal, interest, taxes, insurance, and HOA fees) divided by gross income. The traditional benchmark is 28% or below [4].
Back-end ratio (total DTI): All monthly debts (including housing) divided by gross income. The traditional benchmark is 36% or below [5].
In practice, these "benchmarks" are more like guidelines than rules. The average purchase mortgage DTI in October 2025 was 38.5% [6], well above the 36% ideal. Lenders approve higher ratios regularly, especially with compensating factors.
What Counts as a "Good" DTI
Here's the practical framework:
| DTI Range | What It Means | Lending Implications |
|---|
| Under 36% | Strong | Best rates, widest approval |
| 36%–43% | Manageable | Most conventional loans approve |
| 43%–50% | Elevated | FHA and some conventional with strong credit |
| Above 50% | Strained | Limited options (FHA exception up to 57% with compensating factors) |
The 43% number comes from the Qualified Mortgage (QM) rule, which set that as the standard back-end DTI limit for most conventional loans [7]. But here's the reality: FHA loans regularly approve borrowers up to 50%, and their automated underwriting system (TOTAL Scorecard) can go as high as 57% with strong compensating factors like cash reserves or a large down payment [4].
VA loans are even more flexible. They use a 41% benchmark but prioritize "residual income" (the cash left over after all bills are paid) over the DTI percentage itself [8]. A veteran with a 48% DTI but $800 in monthly residual income might get approved while a civilian with 44% DTI and $200 in residual income gets denied.
The point: DTI matters, but it's not the only thing. Credit score, savings, down payment, and the specific loan program all influence the decision. Don't let a DTI calculator tell you "you're denied" when the reality is more nuanced.
Worked Example: The Average Homebuyer
Borrower profile:
- Name: Sam, age 34
- Gross annual salary: $78,000 ($6,500/month)
- Credit score: 720
Current monthly debts:
- Auto loan: $550
- Student loan: $250
- Credit card minimums: $125
- Total non-housing debt: $925
Proposed mortgage (PITI):
- Principal & interest: $1,600
- Property taxes: $325
- Homeowner's insurance: $175
- Total housing cost: $2,100
The math:
Front-end ratio: $2,100 ÷ $6,500 = 32.3%
(Above the traditional 28% benchmark but well within FHA and most conventional limits.)
Back-end ratio: ($2,100 + $925) ÷ $6,500 = 46.5%
(Above the 43% QM standard. Sam would need an FHA loan with compensating factors, or to reduce debts.)
Sam's situation is common. The housing cost alone is fine. It's the stack of other debts that pushes the total over. If Sam pays off the credit card balances ($125/month freed up), the back-end drops to 44.6%. Still tight, but within FHA approval range.
And here's the part that feels unfair: Sam might pay $550 extra per month on the auto loan to pay it off faster, but the lender only counts the minimum payment. Good financial behavior doesn't always register in the DTI formula.
How to Lower Your DTI
There are only two levers: reduce debt payments or increase income. Everything else is a variation on those themes.
Reduce the Numerator (Debt Payments)
-
Pay off the smallest debt first. Eliminating a $125 credit card minimum drops your DTI immediately. The total balance doesn't matter for DTI purposes; only the monthly payment matters.
-
Refinance existing loans to lower payments. Extending a car loan from 36 to 60 months reduces the monthly payment. This increases total interest paid, but if DTI is the barrier to a mortgage approval, the tradeoff may be worth it strategically. (For more on that tradeoff, see our loan term guide.)
-
Consolidate debts with a personal loan. If you have four credit cards with $125 in combined minimums, a personal loan might replace them with a single $110 payment, reducing your DTI by $15/month. Small, but it matters at the margin.
-
Avoid new debt. Every new loan or credit card with a minimum payment raises your DTI. Don't open a new car loan or credit card in the months before applying for a mortgage.
Increase the Denominator (Income)
-
Include all qualifying income. W-2 salary is obvious, but lenders also count overtime (if consistent for 2+ years), bonuses, freelance income (with tax returns), Social Security, disability, alimony received, and rental income.
-
Add a co-borrower. A spouse's income is added to the denominator, which can dramatically improve DTI. But their debts are added to the numerator too. Do the math both ways.
-
Document a raise. If you recently got a salary increase, bring a current pay stub showing the new amount. Lenders use your most recent documented income.
The Student Loan Complication
Student loans create DTI problems that are uniquely frustrating. Here's why:
If you're on an income-driven repayment (IDR) plan and your credit report shows a $0 monthly payment (because your IDR payment is $0 during deferment or based on income), many lenders won't use $0. They'll impute a payment [3].
FHA rule: Uses the greater of 0.5% of the total loan balance or the actual payment amount.
Conventional (Fannie Mae) rule: Uses 0.5% or 1% of the balance if $0 is reported.
On a $60,000 student loan balance:
- Actual IDR payment: $0/month
- Imputed payment (0.5%): $300/month
- Imputed payment (1%): $600/month
That $300 to $600 phantom payment can make or break a mortgage application. If you're in this situation, the most effective strategy is often to have your loan servicer provide a letter showing your actual IDR payment amount (even if it's $0), which some lenders will accept.
The interaction between student loans and DTI is one of the messiest areas in consumer lending. Different lenders interpret the rules differently. If you're denied, ask a mortgage broker to shop your file to a lender with more favorable student loan DTI calculations.
The Question Nobody Asks: Does Rent Count?
If you're renting and applying for a mortgage, your current rent does not count in your DTI. The new mortgage payment replaces it.
But if you're applying for a car loan or personal loan while renting, your rent usually doesn't count against you either, because most landlords don't report to credit bureaus. The lender can't see it.
This creates an odd situation: someone paying $2,200/month in rent might have a DTI of 20% on paper because the rent isn't counted. Their actual financial picture is much tighter than the ratio suggests. DTI is useful but incomplete. It's a snapshot of what appears on your credit report, not a full picture of your cash flow.
For how DTI interacts with the broader loan application process, including how cosigning affects the cosigner's DTI, our cosigning guide covers the specific math.
If you're working on building your credit score alongside improving your DTI, both numbers matter to lenders, but they measure completely different things.
Your Next Move
- Calculate your DTI right now. Add up your minimum monthly debt payments. Divide by your gross monthly income. If you're above 36%, you know where you stand.
- Pull your credit report (free at AnnualCreditReport.com) and verify the monthly payments listed. If a closed account is still showing a balance, dispute it.
- If you're planning to buy a home, calculate your DTI with the projected mortgage payment included. Use a mortgage calculator to estimate PITI.
- Pay off one small debt before applying for a major loan. Eliminating even a $75/month obligation can shift your DTI enough to matter.
- If student loans are inflating your DTI, get a letter from your servicer documenting your actual monthly payment under your current repayment plan. Bring it to the lender.
References
- Consumer Financial Protection Bureau. (2023). What is a debt-to-income ratio? ConsumerFinance.gov. https://www.consumerfinance.gov/ask-cfpb/what-is-a-debt-to-income-ratio-en-1791/
- NerdWallet. (2025). What Is Debt-to-Income Ratio? How to Calculate DTI. NerdWallet. https://www.nerdwallet.com/article/loans/personal-loans/calculate-debt-income-ratio
- Federal Housing Administration (HUD). (2025). Single Family Housing Policy Handbook 4000.1. HUD.gov. https://www.hud.gov/program_offices/administration/hudclips/handbooks/hsgh
- Federal Housing Administration (HUD). (2025). FHA Handbook: DTI Ratios and Compensating Factors. HUD.gov. https://www.hud.gov/program_offices/administration/hudclips/handbooks/hsgh
- Experian. (2025). What Is a Good Debt-to-Income Ratio? Experian.com. https://www.experian.com
- ICE Mortgage Technology. (2025). October 2025 Mortgage Monitor. ICEMortgageTechnology.com. https://mortgagetech.ice.com/resources/data-reports
- Fannie Mae. (2025). Eligibility Matrix. FannieMae.com. https://singlefamily.fanniemae.com/media/20786/display
- Department of Veterans Affairs. (2025). Lenders Handbook - VA Pamphlet 26-7, Chapter 4. Benefits.VA.gov. https://www.benefits.va.gov/warms/pam26_7.asp
