How Much House Can You Actually Afford? A Complete Guide
By the TidyTally team · Last updated September 15, 2026
"How much house can I afford" and "how much will a lender approve me for" are two different questions, and confusing them is one of the most common ways people end up house-poor. A lender's maximum approval is based on what you can technically qualify for; what you can actually afford comfortably depends on your whole financial picture — savings goals, other debts, and how much breathing room you want in your monthly budget. This guide walks through both sides. For the actual payment math once you've picked a number, our Mortgage Calculator handles the rest.
The 28/36 rule: where lenders start
Most conventional lenders use some version of the 28/36 rule as a starting guideline: your housing payment (principal, interest, taxes, insurance, and any HOA) shouldn't exceed 28% of your gross monthly income, and your total debt payments — housing plus car loans, student loans, credit cards, and anything else — shouldn't exceed 36%. These are guidelines, not hard laws; some loan programs allow higher ratios, especially with strong credit or a larger down payment. But they're a useful sanity check even if a lender would approve you for more.
Why "what you're approved for" isn't "what you can afford"
Lenders calculate your maximum approval based on your income and existing debts at the moment you apply — they don't know about your upcoming wedding, your plan to have kids, or how much you want to keep contributing to retirement. It's entirely possible to be approved for a payment that would technically work on paper but would leave you with no real savings margin. A common rule of thumb worth considering alongside 28/36: after your mortgage payment and other debts, could you still save 15-20% of your income and cover an emergency without stress? If the honest answer is no, the approved amount is probably higher than what actually fits your life.
The down payment trade-off
A larger down payment reduces your loan amount, your monthly payment, and — once you cross 20% — eliminates PMI (private mortgage insurance) entirely, which is often $100-$300+ a month depending on loan size. But there's a real trade-off: draining your entire savings for a bigger down payment can leave you without a cushion for moving costs, repairs, or an emergency right when you've taken on a major new expense. A middle path many buyers land on: put down enough to avoid PMI if it's within reach, while still keeping 3-6 months of expenses in reserve after closing.
The costs that don't show up in the "mortgage payment" number
Property tax and homeowners insurance are usually folded into your monthly payment through escrow, which our Mortgage Calculator accounts for — but several real costs typically aren't: closing costs (commonly 2-5% of the purchase price, due upfront), ongoing maintenance (a commonly cited rule of thumb is budgeting 1-2% of the home's value per year), and the fact that a bigger house usually means bigger utility bills. None of these show up when someone quotes you "the mortgage payment," which is exactly why they catch first-time buyers off guard.
How interest rate changes your real budget
The same home price can mean a dramatically different monthly payment depending on the interest rate environment at the time you buy — a jump from 6% to 7% on a $400,000 loan adds roughly $270 to the monthly payment, which is real money over a 30-year term. This is exactly why it's worth running your numbers at a couple of different rate scenarios rather than a single optimistic one, since rates can move between when you start house-hunting and when you actually close.
A practical way to land on your number
Start with your take-home pay, subtract your other debt payments and savings goals, and see what's genuinely left for housing — then compare that to what the 28/36 rule and a lender's pre-approval would suggest. Where those two numbers land close together, you've likely found a comfortable range. Where they're far apart, it's worth trusting your own budget over the lender's maximum. From there, plug a few realistic home prices and rates into the Mortgage Calculator to see the actual monthly payment, including taxes and insurance, before you start seriously house-hunting.