"How much house can I afford?" is really two questions hiding in one. There's the number a lender will approve you for, and there's the number you'll actually feel good about paying every month. They're rarely the same — and the gap between them is where a lot of buyers get stretched too thin.
The number lenders look at: your DTI
Lenders lean heavily on your debt-to-income ratio (DTI) — your total monthly debt payments divided by your gross monthly income. They look at two versions: the "front-end" (just the new house payment) and the "back-end" (the house payment plus car loans, student loans, credit-card minimums, and other obligations).
Most loan programs want your back-end DTI somewhere under roughly 43–50%, though that ceiling moves around by program and by the strength of the rest of your file. The key insight: paying down a car loan or a credit card before you apply can raise your buying power more than a raise would.
The number that actually matters: your comfort payment
Just because a lender will approve a payment doesn't mean you should take it. Build your number from your real budget. Your full monthly housing cost — principal, interest, property taxes, homeowner's insurance, and any HOA or mortgage insurance (together, "PITI") — plus a cushion for maintenance and the surprises every house eventually throws at you.
What moves your max up or down
- Income — and how it's documented (W-2, 1099, or self-employed all qualify differently)
- Monthly debts — the biggest lever most buyers can actually control
- Down payment — more down means a smaller loan and often no mortgage insurance
- Interest rate and loan program
- Property taxes and insurance — which vary a lot by county and property
Skip the "2.5x your income" rules of thumb. They ignore your actual debts, your down payment, and current rates. The only number worth trusting is one built from your file.
Get your real number
Plug your details into my affordability calculator to see a price range, or use the payment calculator to test a specific home. Then let's talk — I'll run a real pre-approval so your number is one sellers can trust, not a guess.
This article is general education, not a commitment to lend or an offer of credit. Program availability, terms, rates, and qualification guidelines vary by lender and are subject to change; all loans are subject to underwriting and final approval. Market figures are approximate and change over time. For guidance specific to your situation, reach out directly. Garrett Potz, NMLS #631592 · Affinity Home Lending, Company NMLS #1181151 · Equal Housing Lender.