What Is DTI and Why Does It Matter?
DTI stands for debt-to-income ratio. It compares your total monthly debt obligations to your gross monthly income (before taxes). Lenders use it to assess whether you can comfortably handle a new mortgage payment on top of your existing obligations.
DTI is expressed as a percentage. A DTI of 36% means 36 cents of every dollar you earn goes toward debt payments. Most mortgage lenders have a maximum DTI — typically 43–45% — above which they won't approve a loan.
How to Calculate Your DTI
The formula is simple:
DTI = (Total Monthly Debt Payments ÷ Gross Monthly Income) × 100
Step 1: Add Up Your Monthly Debt Payments
Include all recurring debt obligations that appear on your credit report:
- Minimum monthly credit card payments (not your balance — the minimum payment)
- Car loan or lease payments
- Student loan payments (even if in deferment — lenders still count them)
- Personal loan payments
- Child support or alimony payments
- Any other loan payments (boat, RV, etc.)
- Your proposed new mortgage payment (principal, interest, taxes, insurance, and PMI if applicable)
Do NOT include: utilities, groceries, cell phone, streaming subscriptions, or insurance premiums. These are monthly expenses but not debt payments.
Step 2: Determine Your Gross Monthly Income
Use your gross income — before taxes, not your take-home pay. Include:
- Salary or wages (annual salary ÷ 12)
- Self-employment income (use 2-year average, after business expenses)
- Rental income (typically 75% of gross rent to account for vacancy)
- Social Security, pension, or disability income
- Child support or alimony received (if it will continue for 3+ years)
- Part-time or second job income (if you've held it for 2+ years)
Bonuses and overtime income can count, but lenders typically require a 2-year history of receiving them and will average the amounts.
Step 3: Divide and Multiply
Example: You earn $6,000/month gross. Your monthly debts are: car loan $450, student loans $250, credit card minimums $100. Your proposed mortgage payment (PITI) is $1,700.
- Total monthly debts: $450 + $250 + $100 + $1,700 = $2,500
- DTI = $2,500 ÷ $6,000 = 0.417 = 41.7%
Front-End vs Back-End DTI
Lenders actually look at two DTI figures:
Front-End DTI (Housing Ratio)
This includes only your housing costs — mortgage payment (principal and interest), property taxes, homeowner's insurance, and PMI if applicable. Lenders typically want this below 28% of gross income.
Example: $6,000/month income. $1,700 mortgage payment. Front-end DTI = $1,700 ÷ $6,000 = 28.3%.
Back-End DTI (Total DTI)
This includes housing costs PLUS all other monthly debt payments. This is the number most people refer to as "DTI." Lenders typically cap this at 43–45%, though some programs allow up to 50% with compensating factors.
Most lenders prioritize back-end DTI. If your back-end DTI is within limits, a front-end ratio slightly above 28% is usually acceptable.
DTI Limits by Loan Type
- Conventional loans: Maximum back-end DTI of 45%, or up to 50% with strong compensating factors (high credit score, large down payment, significant reserves)
- FHA loans: Maximum 43% DTI for most lenders, though FHA technically allows up to 57% with compensating factors
- VA loans: No hard maximum, but lenders typically prefer under 41%. VA uses a residual income test alongside DTI
- USDA loans: Maximum 41% DTI, with some flexibility up to 44% with compensating factors
- Jumbo loans: Typically stricter — most require 43% or less, often 36–40% for larger loan amounts
What DTI Do You Need to Get the Best Terms?
Getting approved is one thing — getting approved on favorable terms is another. While lenders will approve mortgages up to 43–45% DTI, a lower DTI often results in:
- More lender options (some lenders won't go above 36–38%)
- Easier underwriting and approval process
- More flexibility on other risk factors (lower credit score, smaller down payment)
- Better rates in some cases
A DTI under 36% is considered strong. Under 28% is excellent. Above 43%, you may find approval difficult or limited to certain loan programs.
How to Lower Your DTI
If your DTI is too high to qualify — or you want to qualify for a larger loan — there are two levers: reduce debts or increase income.
Pay Down Existing Debts
Focus on eliminating smaller loans completely. Paying off a $4,000 car loan you have 8 months left on eliminates a $500/month payment from your DTI calculation. That $500 reduction can meaningfully change what you qualify for.
Credit card minimum payments are also powerful to eliminate. If you have three cards with $100 minimum payments each, paying them off removes $300 from your monthly debt total.
Student loans in deferment still count in most DTI calculations. If you can switch to income-based repayment to lower the monthly payment, that reduces your DTI even while keeping the debt.
Increase Your Income
Additional income that can be documented and has a history of at least 2 years can be added to your qualifying income. Part-time work, freelance income, rental income, or a raise all help. Note that lenders typically want to see a 2-year paper trail — you can't start a side business the month before applying and have that income count.
Buy a Less Expensive Home
The most direct lever: a lower purchase price means a smaller mortgage payment, which directly reduces your back-end DTI. Running the numbers at different price points with our Affordability Calculator shows exactly how much house you can support at different DTI levels.
Make a Larger Down Payment
More down payment = smaller loan = smaller mortgage payment = lower DTI. This also eliminates PMI at 20%, further reducing the housing payment component of your DTI.
DTI vs Credit Score: Which Matters More?
Both matter, but they affect different aspects of your mortgage. Credit score primarily determines your interest rate. DTI primarily determines how much you can borrow. A high credit score won't save you if your DTI is too high — you simply won't qualify. And a low DTI won't get you a good rate if your credit score is poor.
Think of it this way: credit score is about creditworthiness (will you repay?), DTI is about capacity (can you afford to repay?). Lenders need both boxes checked.
Calculate Your DTI and Home Budget
Our free Affordability Calculator calculates your DTI automatically based on your income and existing debts, then shows you the maximum home price you can afford while staying within lender guidelines. Enter your numbers to see exactly where you stand.
Key Takeaways
- DTI = total monthly debt payments ÷ gross monthly income × 100
- Front-end DTI is housing costs only; back-end DTI includes all debts
- Most lenders cap back-end DTI at 43–45%
- A DTI under 36% is considered strong and opens up the most lender options
- Paying off small loans completely is often the fastest way to lower DTI
- Student loans in deferment still count against your DTI in most cases