Debt-to-income ratio calculation for Texas mortgage qualification
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DTI Math: The Ratio That Actually Decides Your Texas Mortgage

ByAnthony Ferrando

The median home price in Austin is hovering around $550,000 heading into summer 2026. At today’s rates, that translates to a housing payment close to $4,000 per month. The number that tells a lender whether you can handle that payment has nothing to do with your credit score alone. It’s your debt-to-income ratio, and understanding it before you start shopping can save you weeks of frustration.

Your DTI (debt-to-income) ratio is the figure underwriters use to decide whether your income supports the mortgage you’re asking for. It’s the most common reason Austin buyers find out they qualify for less than expected, or don’t qualify at all on their first application. Getting clear on your DTI before you talk to a seller’s agent keeps your expectations calibrated and your pre-approval accurate.

Key takeaways:

  • Back-end DTI is the primary qualifying number for most loan programs
  • Conventional loans typically cap at 45%; FHA allows up to 50%+ with compensating factors
  • Minimum credit card payments count, not full balances
  • Student loans in deferment may still count at 0.5%-1% of the outstanding balance

What Is Debt-to-Income Ratio?

DTI is a percentage that compares your total monthly debt obligations to your gross (pre-tax) monthly income. The formula:

DTI = Total Monthly Debt Payments divided by Gross Monthly Income, times 100

If you earn $9,000 per month before taxes and your total monthly debt payments add up to $3,600, your DTI is 40%.

Lenders calculate two versions:

  • Front-end DTI: Your proposed housing payment only (principal plus interest plus property taxes plus homeowner’s insurance plus any HOA dues), divided by gross monthly income.
  • Back-end DTI: Your proposed housing payment plus all other monthly debt obligations, divided by gross monthly income. This is the number most lenders focus on for qualifying purposes.

What Counts as Monthly Debt in the Calculation?

This is where buyers often underestimate their DTI. Lenders count every liability that appears on your credit report with at least 10 months of payments remaining.

Counted in your DTI:

  • Auto loan payments
  • Student loan payments (if deferred, lenders typically count a calculated payment of 0.5%-1% of the outstanding balance per month, depending on loan program)
  • Minimum credit card payments (not full balances, just the minimums)
  • Personal loans
  • Child support or alimony
  • Co-signed loans you’re liable for
  • Any installment debt with 10 or more months remaining

Not counted in DTI:

  • Utilities
  • Cell phone bills
  • Subscriptions (streaming services, gym memberships)
  • Car insurance
  • Groceries and everyday expenses
  • Retirement contributions

One important note for self-employed borrowers: your income side of the equation is calculated differently. Lenders use your net income from tax returns averaged over two years, not your gross receipts. If you run your own business in Austin, understanding how lenders calculate self-employed income is worth reading before you run DTI numbers.

What DTI Do You Need to Qualify?

Different loan programs have different thresholds:

  • Conventional loans: Most lenders want a back-end DTI at or below 45%. Automated underwriting systems (Fannie Mae Desktop Underwriter, Freddie Mac Loan Product Advisor) may approve up to 50% with strong compensating factors such as large cash reserves, excellent credit, or a larger down payment.
  • FHA loans: The FHA allows back-end DTI up to 57% with compensating factors. Most lenders apply overlays closer to 50%. Standard approvals typically fall between 43%-50%.
  • VA loans: No hard DTI ceiling, but the VA flags files above 41% for residual income analysis. Strong residual income (money left over after all monthly obligations) allows higher DTIs to close.
  • Jumbo loans: Typically stricter, with most lenders targeting 43% or below for loan amounts above the conforming limit ($806,500 in Travis County for 2026).

These are starting points, not guarantees. Your actual limit depends on your full file: credit score, reserves, loan type, down payment, and how automated underwriting scores your application.

Running the Numbers on an Austin Purchase

A buyer earns $10,500 per month gross (approximately $126,000 per year). Current debts: a $430 per month car payment and $300 per month in student loan payments. No credit card balances. Total existing monthly debt: $730.

They’re considering a home at $545,000 with 5% down. At 6.57% on a 30-year fixed, the principal and interest payment is approximately $3,360 per month. Adding estimated property tax ($785 per month based on Travis County’s roughly 1.75% effective rate) and homeowner’s insurance ($155 per month): total housing payment is around $4,300 per month.

Back-end DTI: ($4,300 plus $730) divided by $10,500 equals 48%. That’s above the 45% conventional threshold.

Options:

  1. Pay off the car loan before applying. Back-end DTI drops to ($4,300 plus $300) divided by $10,500 = 44%. Under the conventional ceiling.
  2. Reduce the purchase price to $490,000. Housing payment becomes about $3,890. DTI: ($3,890 plus $730) divided by $10,500 = 44%.
  3. Use an FHA loan, which accommodates DTIs up to 50% with compensating factors. At 48% with a clean credit file, FHA approval is realistic.

Understanding how down payment amounts vary by price tier in Travis County also affects the calculation, since a lower loan amount reduces the housing payment directly.

How to Lower Your DTI Before You Apply

Pay off installment loans. Eliminating a car payment or personal loan removes a monthly line item entirely. A $430 per month car payoff improves DTI by about 4 percentage points on a $10,500 income, which can make the difference between approval and denial at high Austin purchase prices.

Pay down credit card balances strategically. Every $50 reduction in your minimum monthly credit card payment improves DTI slightly. To move the needle significantly, aim to zero out a card rather than just reduce the balance.

Increase documented income. A recent raise documented with a new pay stub and offer letter shifts the ratio immediately. Additional income sources can count if documented for at least two years on tax returns.

Adjust your purchase price target. Buying a $450,000 home instead of $550,000 reduces the proposed housing payment by $700-$900 per month at current rates. That single change can solve a DTI problem without touching your debt profile at all.

Before submitting offers, working through a full pre-approval (not just pre-qualification) shows you your exact DTI ceiling. That’s the number worth knowing before a seller’s agent sees your name.

Frequently Asked Questions

What is a good DTI ratio for a mortgage in Texas?

Most conventional lenders want a back-end DTI at or below 45%. FHA loans allow up to 50% or higher with compensating factors. If your DTI is below 36%, you’re in strong qualifying territory and may access better pricing on some programs. A DTI above 50% makes qualifying difficult with most lenders and loan types in Texas.

Does student loan debt count against my DTI for a Texas mortgage?

Yes. Student loan payments count toward your back-end DTI. If your loans are in deferment or income-driven repayment, lenders may still calculate a payment for DTI purposes, typically 0.5% to 1% of the outstanding balance per month depending on loan program. A $60,000 student loan in deferment could still add $300-$600 to your monthly debt figure for qualifying.

Can I still buy a home in Austin if my DTI is above 45%?

Yes, depending on the loan program and your compensating factors. FHA loans allow higher DTIs and are common in Austin for buyers with elevated ratios. A strong credit score (740+), significant cash reserves, or a larger down payment can also push the approved DTI ceiling higher on conventional loans through automated underwriting. The best path is to run your actual file with a licensed loan officer.

Does my credit card balance or just the minimum payment count in my DTI?

Lenders use the minimum monthly payment from your credit report, not the full balance. If your minimum payment is $75 per month on a $5,000 balance, only $75 counts toward your DTI. A high credit card balance also affects your credit score through utilization, which can indirectly affect the rate you’re offered.

How does property tax affect my DTI in Travis County?

Property taxes are included in your front-end and back-end DTI calculation because they’re part of your monthly PITI (principal, interest, taxes, insurance) payment. Travis County’s effective property tax rate is approximately 1.7%-1.9% depending on the taxing jurisdiction. On a $550,000 home, that translates to roughly $775-$875 per month in property tax added directly to your housing payment in the DTI calculation.

What is the fastest way to lower my DTI before applying for a mortgage?

Paying off an installment loan entirely (auto loan, personal loan) is typically the fastest path because it removes a monthly payment line item rather than just reducing it. Paying down a credit card to zero has a similar effect if the minimum payment was significant. Both approaches take effect on your next credit report update, which lenders pull at application.

If you want to run these numbers for your specific situation, schedule a discovery call and we’ll walk through your DTI, your price range, and your loan options together. No pressure, no commitment, just clarity on where you stand.

Ferrando Financial LLC | NMLS# 2403080 | Licensed in Texas. This content is for educational purposes only and does not constitute a commitment to lend. Loan approval is subject to credit, income, and property qualification. Rate and payment examples are illustrative, not a quote.

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