The question isn't just "how much will the bank lend me?" Banks will approve you for more than you should actually spend. The real question is how much house fits comfortably inside your financial life without crowding out everything else — savings, retirement contributions, emergencies, the cost of actually living. That number is almost always lower than your maximum approval amount, and figuring it out before you start shopping is one of the most valuable things you can do for your financial future.
Start With Your Gross Income — Then Reality-Check It
The most widely cited affordability rule is that your housing costs shouldn't exceed 28% of your gross monthly income. Gross income means before taxes, before retirement contributions, before health insurance deductions. If you earn $80,000 per year, your gross monthly income is about $6,667 — and 28% of that is $1,867. That's the rough ceiling on your total monthly housing payment, including your mortgage principal and interest, property taxes, and homeowner's insurance.
That 28% figure comes from conventional mortgage underwriting guidelines and is sometimes called the "front-end ratio." It's a useful starting point, but it's not the whole picture. A person earning $80,000 in a high-cost-of-living city with significant student loan debt and a car payment is in a completely different position than someone earning the same amount in a lower-cost area with no other obligations. The rule gives you a ceiling; your actual financial situation gives you the real number.
There's also a broader ratio called the "back-end ratio" or debt-to-income ratio (DTI), which includes all your monthly debt payments — mortgage, car loans, student loans, credit cards — divided by your gross monthly income. Most lenders want this below 43%, and many prefer below 36%. If you already carry significant debt, your mortgage affordability drops considerably even if your income is solid.
The Real Cost of Owning a Home
The mortgage payment is the most visible cost, but it's not the only one — and the others add up faster than most first-time buyers expect. Before you commit to a purchase price, you need to account for the full monthly cost of ownership, not just the mortgage.
Property taxes vary significantly by location but typically run 0.5% to 2.5% of the home's assessed value annually. On a $400,000 home in a state with a 1.2% effective property tax rate, that's $4,800 per year — or $400 per month added to your payment. In high-tax states like New Jersey or Illinois, the number can be substantially higher.
Homeowner's insurance typically costs $1,000–$2,000 per year for a median-priced home, depending on location, the home's age, and coverage levels. In areas prone to flooding or wildfires, insurance can be significantly more expensive — and in some high-risk areas, private coverage has become difficult to obtain at any price.
HOA fees, if applicable, can range from $100 to $500 or more per month depending on the community and what's included. Many condos and planned communities require them, and they're non-negotiable once you own.
Maintenance and repairs are the most underestimated ongoing cost of homeownership. A commonly used rule of thumb is to budget 1% of the home's value per year for maintenance — meaning a $400,000 home should have roughly $4,000 per year, or $333 per month, set aside for repairs. Older homes, homes with aging roofs or HVAC systems, and homes in climates with harsh winters often require more.
Add all of these together, and the true monthly cost of a $400,000 home can easily be $500–$800 more than the mortgage payment alone. Running your numbers with the full cost — not just the mortgage — is the only honest way to assess what you can afford.
What the Numbers Look Like at Different Income Levels
It helps to see how the math plays out concretely rather than abstractly. The following scenarios use a 30-year fixed mortgage at a hypothetical 7% interest rate, a 10% down payment, and approximate property taxes and insurance to illustrate realistic total monthly costs at different income levels. These are illustrative figures, not quotes — your actual rate, taxes, and insurance will vary by location and credit profile.
Income: $60,000/year ($5,000/month gross) The 28% front-end guideline puts your maximum total housing payment at around $1,400 per month. At 7% on a 30-year loan with 10% down, that roughly corresponds to a purchase price in the $175,000–$200,000 range, depending on your local property tax rate. In many US metros, this is a difficult price point to buy into. It reflects the real challenge facing buyers in the lower-middle income range in most markets.
Income: $90,000/year ($7,500/month gross) At 28%, your ceiling is around $2,100 per month in total housing costs. With a 10% down payment, that puts a purchase price in the $270,000–$310,000 range within reach, depending on taxes and insurance. This is a more viable range in many mid-size US cities and suburban markets.
Income: $130,000/year ($10,833/month gross) At 28%, you're looking at roughly $3,033 per month in total housing costs. That opens up a purchase price range of approximately $380,000–$430,000 — enough for a solid home in most markets, though still tight in high-cost metros like New York, San Francisco, or Boston.
These scenarios assume no other significant debt. If you're carrying student loans or a car payment, the numbers shift downward. Running your own numbers with a mortgage calculator that includes taxes, insurance, and PMI (if your down payment is under 20%) will give you a more accurate picture than any rule of thumb.
The Down Payment Changes Everything
How much you put down affects your monthly payment, your interest rate, and whether you'll owe private mortgage insurance (PMI). PMI is required by most lenders when your down payment is less than 20%, and it typically adds 0.5%–1.5% of the loan amount per year to your payment. On a $350,000 loan, that's $1,750–$5,250 per year — or roughly $145–$435 per month — on top of everything else, and it provides no direct benefit to you as the buyer.
A larger down payment reduces your monthly payment, eliminates PMI, and often qualifies you for a better interest rate. The trade-off is that it requires more cash upfront, which takes time to save and means keeping that money out of other investments. The right down payment amount depends on your personal cash position, how long you plan to stay in the home, and your local market. In competitive markets where offers need to be strong, a larger down payment may also improve your offer's attractiveness to sellers.
The minimum down payment for a conventional loan is 3–5% for qualified buyers. FHA loans allow as little as 3.5% down. These low-down-payment options make homeownership accessible sooner, but they come with higher ongoing costs that are worth factoring into your affordability calculation honestly.
The Number the Bank Gives You vs. the Number You Should Spend
Lenders will often approve you for significantly more than you should actually borrow. That's not a knock on lenders — it's simply that their approval criteria are based on whether you can mathematically make the payment, not whether doing so is consistent with your other financial goals.
Being "house poor" — owning a home that consumes so much of your income that you can't save adequately, fund retirement, handle emergencies, or enjoy your life — is a real and common outcome of buying at the top of your approval range. The mortgage gets made. Retirement contributions get paused. The emergency fund never gets built. When the car breaks down or the HVAC fails, the credit card comes out.
A conservative approach is to target a monthly housing cost no higher than 25% of your take-home (after-tax) pay rather than 28% of gross. This is stricter than conventional guidelines, but it leaves meaningful room for savings, retirement contributions, and financial flexibility. If that ratio keeps you from the home you want in your current market, it's worth asking whether now is the right time to buy, whether a different location offers better value, or whether additional time saving for a larger down payment changes the picture.
What to Do Before You Start Shopping
Getting clear on your real affordability number before you look at a single listing protects you from the emotional pull that comes once you've found a home you love. A few practical steps make a real difference.
Pull your credit report and know your credit score before talking to any lender. Your interest rate — which significantly affects what you can afford — depends heavily on your credit profile. Improving your score before applying, even by a modest amount, can translate to meaningful savings over a 30-year loan.
Calculate your actual take-home pay after all deductions, not your gross salary. Then build a budget that includes your existing debt payments, your savings and retirement contribution targets, and your regular living expenses. What's left after all of that is what you can honestly put toward housing — not the number a calculator spits out based on gross income alone.
Get pre-approved (not just pre-qualified) by a lender before you start shopping. Pre-approval gives you a realistic loan amount, identifies any credit or documentation issues early, and makes your offers stronger when you do find the right home. Just remember that the pre-approval amount is a ceiling set by the lender, not a recommendation.
Key Takeaways
The 28% gross income rule is a starting point, not a final answer. Your real number depends on your full financial picture — existing debt, down payment size, local property taxes, and how much room you want for savings and flexibility. The true monthly cost of owning includes taxes, insurance, HOA fees, and maintenance — always calculate total cost, not just mortgage payment. Buying below your maximum approval amount isn't settling; it's financial wisdom that protects your quality of life for years to come.
FAQ
Does the 28% rule apply to net income or gross income? Conventional mortgage guidelines use gross income (before taxes and deductions). Using net take-home pay as your basis instead — which is what the stricter 25% rule does — gives you a more conservative and often more realistic affordability estimate, since your actual spendable income is your after-tax figure.
How much should I have saved before buying a home? Beyond the down payment, you should have enough cash for closing costs (typically 2–5% of the purchase price), a move-in and immediate repair buffer (at least $5,000–$10,000), and a healthy emergency fund covering 3–6 months of expenses — all kept separate from your down payment. Running out of cash at closing or in the first months of ownership is a preventable risk with adequate preparation.
Should I buy as much house as I can afford or stay conservative? Staying conservative — buying below your maximum affordability — gives you financial breathing room that most homeowners are glad to have. Your income may grow, your situation may change, and having a payment that's comfortable rather than maxed-out makes those transitions much less stressful. Many experienced homeowners wish they'd bought less house on their first purchase.
How does a higher interest rate affect affordability? Significantly. At 4% interest, a $300,000 mortgage costs about $1,432 per month in principal and interest. At 7%, that same loan costs about $1,996 per month — a difference of $564 per month, or nearly $6,800 per year. Higher rates effectively reduce how much home your income can support without increasing your payment. Running your numbers at current market rates, not historical lows, is essential for an accurate affordability picture.
Buying a home is one of the biggest financial decisions you'll make, and the difference between buying at 25% of take-home pay versus 35% compounds in ways that affect your financial security for decades. Know your real number before you start looking — and trust it when the market, lenders, or real estate agents push you toward the top of your range.
📚 Sources
Consumer Financial Protection Bureau – How Much House Can I Afford?: https://www.consumerfinance.gov/ask-cfpb/how-much-house-can-i-afford-en-1688/
Fannie Mae – HomeReady Mortgage and Income Guidelines: https://singlefamily.fanniemae.com/originating-underwriting/mortgage-products/homeready-mortgage
HUD – Buying a Home: https://www.hud.gov/topics/buying_a_home
Freddie Mac – How Much House Can You Afford: https://www.freddiemac.com/blog/homebuying/20190301_how_much_house_can_you_afford
NerdWallet – Home Affordability Calculator: https://www.nerdwallet.com/mortgages/how-much-house-can-i-afford
Urban Institute – Housing Finance Policy Center: https://www.urban.org/policy-centers/housing-finance-policy-center
IRS – Mortgage Interest Deduction: https://www.irs.gov/taxtopics/tc505
