Debt-to-Income Ratio (DTI) Explained | Todd Uzzell Mortgage
Arizona Mortgage Guide — Todd Uzzell NMLS #1525192

Debt-to-Income Ratio
Explained

DTI is the single most important number lenders look at after your credit score. Here is exactly how it works, what ratios qualify for each loan type, and how to improve yours before you apply.

The DTI Formula
Total Monthly Debt Payments Gross Monthly Income = DTI %

Example: $2,100 monthly debts ÷ $6,000 gross income = 35% DTI

What Is Debt-to-Income Ratio?

Debt-to-income ratio — or DTI — is a percentage that compares how much you owe every month to how much you earn. Lenders use it to measure whether you can realistically afford a mortgage payment on top of your existing obligations.

Unlike credit score, which measures how reliably you have paid debts in the past, DTI measures whether you can afford the new payment going forward. A borrower with a 750 credit score and a 55% DTI is often a harder approval than a borrower with a 680 score and a 32% DTI.

There are two types of DTI that lenders look at:

Front-End DTI

Housing costs only — your new mortgage payment (principal, interest, taxes, insurance, HOA) divided by gross income. FHA caps this at 31%. Also called the "housing ratio."

Back-End DTI

All monthly debts plus your housing payment, divided by gross income. This is the number lenders focus on most. When a lender says "your DTI is 42%," they mean back-end DTI.

What Is a Good DTI Ratio?

Here is how lenders generally interpret DTI ranges:

Excellent
Under 36%
< 36%
Good
36–43%
36–43%
Manageable
43–50%
43–50%
High Risk
Above 50%
> 50%

Most conventional lenders prefer to see back-end DTI at or below 43-45%. Falling under 36% typically unlocks the best rates and easiest approvals across all loan types.

DTI Limits by Loan Type

Each loan program has its own DTI rules — and some are significantly more flexible than others:

Loan TypeFront-End MaxBack-End MaxFlexibility
ConventionalNo hard limit45–50%Automated underwriting (DU/LP) makes the call
FHA31%43–57%Up to 57% with compensating factors
VANo hard limit41% (guideline)No hard cap — residual income matters more
USDA29%41%Stricter than FHA/VA; less flexibility
JumboNo hard limit36–43%Stricter — varies by lender
Non-QMNo limitVaries widelyMost flexible — lender-specific
Note on VA Loans: VA doesn't use DTI the same way other programs do. Instead, VA focuses heavily on "residual income" — how much money you have left over after all obligations. A veteran with 55% DTI but strong residual income may still get approved where other programs would decline.

What Counts Toward DTI?

Lenders are very specific about what goes into the DTI calculation. Many borrowers are surprised to learn what is and isn't included:

✗ Counts Against DTI

  • Proposed mortgage payment (PITI + HOA)
  • Car loan payments
  • Student loan payments (sometimes even if deferred)
  • Minimum credit card payments
  • Personal loan payments
  • Child support / alimony
  • Co-signed loan payments
  • Installment loans (furniture, equipment)

✓ Does NOT Count Against DTI

  • Utilities (electric, gas, water)
  • Cell phone bill
  • Groceries and food
  • Health insurance premiums
  • Car insurance
  • Streaming subscriptions
  • Gym memberships
  • Property taxes (already in PITI)
Student Loans — Important: Even if your student loans are in deferment, most lenders still count a payment toward your DTI. FHA uses either the actual payment or 1% of the balance per month (whichever is greater). Conventional loans use the actual payment or 1% of balance. This surprises many first-time buyers.

Calculate Your DTI

Use this quick calculator to estimate your current debt-to-income ratio before applying for a mortgage.

DTI Calculator

How to Lower Your DTI Before Applying

If your DTI is too high, there are concrete steps you can take before applying. Some have immediate impact, others take a few months:

💳 Pay Off Small Installment Loans

A car loan with 6 payments left at $400/month is costing you 400 points of DTI. Paying it off immediately drops your DTI by the full payment amount. Focus on loans with small remaining balances — biggest DTI impact per dollar spent.

🚫 Do Not Take On New Debt

Avoid financing a car, opening new credit accounts, or taking personal loans in the 3-6 months before applying. New debt raises your monthly obligations and can disqualify you even after pre-approval if taken between contract and closing.

📈 Document All Income Sources

Every dollar of documented income lowers your DTI. Overtime, bonuses, rental income, side business income, and second job income can all count — if it's documented and consistent for 2 years. Undocumented income cannot be used.

💰 Pay Down Credit Card Balances

Credit card minimum payments are calculated as a percentage of your balance. Paying balances down reduces your required minimum payment, which lowers your DTI. Bonus: lower utilization also improves your credit score.

🏠 Consider a Smaller Purchase Price

Targeting a home at a lower price point reduces the mortgage payment, which is the largest component of your DTI. Sometimes buying at $350K instead of $400K makes all the difference between approval and denial.

✂️ Do Not Close Old Credit Cards

Closing cards does not help your DTI (only the minimum payment counts, not the balance). But closing cards can hurt your credit score by reducing available credit. Leave old accounts open — especially ones with no annual fee.

Frequently Asked Questions

What is a good debt-to-income ratio for a mortgage?
Most lenders prefer a total back-end DTI of 43% or lower. Under 36% is considered excellent and typically qualifies for the best rates. Conventional loans can go to 45-50% with strong compensating factors, FHA can stretch to 57% in some cases, and VA focuses on residual income rather than a hard DTI cap.
Does student loan debt count against my DTI even if deferred?
Usually yes. FHA requires lenders to use either the actual payment or 1% of the outstanding balance per month, whichever is greater. Conventional loans use the actual payment or 0.5-1% of the balance depending on the program. This is one of the biggest surprises for first-time buyers — deferred loans still count.
Can co-signed loans affect my DTI?
Yes. If you are a co-signer on someone else's loan, that payment counts toward your DTI — even if the primary borrower is making all the payments. The exception: if you can document 12 consecutive months of the primary borrower making the payments from their own account, some lenders will exclude it.
Is gross or net income used for DTI calculation?
Gross income — before taxes and other deductions. This is the income figure that appears on your pay stubs or tax returns before any withholding. Self-employed borrowers typically use net income from Schedule C or adjusted gross income from tax returns, which is why DTI can look different for self-employed buyers.
Can I get a mortgage in Arizona with a 50% DTI?
It depends on the loan type. FHA allows up to 57% with strong compensating factors (high credit score, significant reserves). Some conventional programs allow up to 50%. VA has no hard cap. Non-QM lenders can sometimes accommodate higher DTI ratios. Call Todd Uzzell at 480-330-1724 to review your specific situation — there are often more options than borrowers realize.
What is the DTI limit for an Arizona FHA loan?
FHA guidelines allow a front-end DTI of 31% and back-end DTI of 43% as standard. With strong compensating factors — such as a credit score above 680, significant cash reserves, or a history of low housing expense relative to income — FHA can approve DTI ratios up to 57% through automated underwriting.
Todd Uzzell NMLS #1525192
Todd Uzzell
Licensed Arizona Mortgage Lender · NMLS #1525192

20+ years helping Arizona buyers navigate mortgage qualification. Starboard Financial NMLS #156931, License BK-0910725. 4145 East Baseline Road, Gilbert AZ 85234. 480-330-1724.

Know Your DTI Before You Apply

Todd will run your actual numbers — income, debts, and loan scenarios — and show you exactly where you stand before you start shopping.

Get Pre-Approved → 📞 480-330-1724

NMLS #1525192 · Starboard Financial NMLS #156931 · Equal Housing Lender · Not a guarantee of financing

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