Introduction
"How much house can I afford?" sounds like a simple question with a simple answer. Plug your income into a calculator, get a number, and start shopping.
If only it were that easy.
The reality is that "how much you can afford" has at least three different answers depending on who's doing the calculating. Your lender will give you one number. A mortgage calculator will give you another. And if you're honest with yourself about your actual life, your real number is probably different from both of those.
This article is about finding that third number, the one that lets you own a home comfortably, live your life fully, and not spend the next decade feeling financially strangled by a decision you made in a moment of optimism.
The Three Numbers (and Why They're Different)
What the Lender Will Approve
Lenders determine how much to lend you using your gross income (before taxes), your existing monthly debts, and your credit score. Most conventional lenders use a maximum debt-to-income ratio of 43%, meaning your total monthly debt payments, including the new mortgage, can't exceed 43% of your gross monthly income.
On a $120,000 gross annual income (about $10,000 per month), 43% is $4,300. If you have $500 in existing debt payments, your maximum mortgage payment under this guideline would be around $3,800 per month. At today's rates, that could support a loan of roughly $550,000 to $650,000, depending on the rate.
That's what you can borrow. It tells you almost nothing about what you should borrow.
What a Mortgage Calculator Says
Mortgage calculators give you a monthly payment estimate based on loan amount, interest rate, and loan term. They're useful for comparing scenarios, but typically don't include property taxes, insurance, HOA fees, PMI, or maintenance costs. What looks like a manageable payment in the calculator can be significantly higher in reality once all costs are included.
What You Can Actually Afford
Your real affordability number is based on your take-home pay (after taxes and other deductions), your actual monthly expenses, your savings goals, and what's left over for housing costs after everything else is accounted for. This is almost always lower than what the lender will approve, and it's the number that should drive your home search.
Start with Your Take-Home Pay
Your lender uses gross income. You should use net income, what actually hits your bank account after federal and state taxes, Social Security, Medicare, health insurance premiums, and retirement contributions.
For many people, take-home pay is 65% to 75% of gross income. On that $120,000 gross salary, you might actually bring home $7,500 to $8,500 per month. That's a meaningful gap from the $10,000 the lender is calculating against.
Add up all your actual monthly take-home income. If you have a partner or co-buyer, include theirs as well. This is your starting point.
Account for Everything You Actually Spend
Go through three months of bank and credit card statements and tally your real monthly expenses. Include everything:
- Food (groceries and restaurants)
- Transportation (car payment, insurance, gas, parking, transit)
- Healthcare (premiums, copays, prescriptions)
- Subscriptions and memberships
- Student loan payments
- Credit card minimums
- Childcare or pet care
- Entertainment and hobbies
- Clothing and personal care
- Travel and vacations (annualized and divided by 12)
- Gifts and celebrations
Be honest. Don't use an idealized version of your spending. Use your actual spending. The goal is to know what your life really costs so you can figure out what's left for housing.
Protect Your Savings Goals
Before you calculate what you can spend on housing, decide what you need to keep saving for. This includes:
- Retirement contributions (at least enough to capture any employer match)
- Emergency fund (three to six months of expenses, if you don't already have it)
- Other goals (kids' education, travel, career investments, etc.)
Homeownership builds equity over time, but it's not a substitute for liquid savings or retirement accounts. Many buyers make the mistake of gutting their financial cushion to buy a home and then feeling permanently strapped. Protecting these savings upfront is essential.
Calculate Your Maximum Housing Budget
Subtract your monthly expenses and savings contributions from your take-home income. What remains is the maximum you could put toward total housing costs.
Total housing costs include more than just the mortgage principal and interest. A complete monthly housing budget looks like this:
- Mortgage principal and interest
- Property taxes (estimate based on your target area; these vary significantly by location)
- Homeowners insurance (typically $100 to $200 per month for most homes)
- HOA fees if applicable
- PMI if your down payment is less than 20% (typically 0.5% to 1.5% of the loan annually)
- Maintenance reserve (budget 1% of the home's value per year, divided by 12)
The mortgage payment itself often represents only 70% to 80% of the total monthly cost of homeownership. Make sure your budget accounts for everything, not just the headline payment.
Work Backward to a Purchase Price
Once you know your maximum comfortable monthly housing cost, you can use a mortgage calculator to work backward to a purchase price. Here's a simplified example:
Say you've determined you can comfortably spend $2,500 per month on total housing costs. You estimate property taxes at $400 per month, insurance at $120, and maintenance reserve at $200, leaving roughly $1,780 for principal, interest, and PMI.
At a 7% interest rate with 5% down, that $1,780 payment (before PMI) would support a loan of roughly $270,000, putting your purchase price around $285,000.
That's your real budget ceiling, arrived at from your actual life, not from a lender's formula.
Common Affordability Mistakes
Buying at the Top of Your Pre-Approval
Your pre-approval amount is the maximum the lender will give you, not the amount you should spend. Many buyers feel pressure to use the full amount, especially in competitive markets where they keep losing offers on lower-priced homes. Resist this. Buying at your maximum leaves you with no financial margin for anything.
Forgetting About Upfront Costs
The down payment and closing costs aren't the only upfront expenses. Moving costs, immediate repairs or updates, new furniture, and the general expense of setting up a home add up quickly. Budget for these separately from your down payment so you're not depleted on day one.
Underestimating Maintenance
New homeowners consistently underestimate how much maintaining a home costs. The 1% annual rule is a guideline, not a ceiling. Older homes, homes with aging systems, and homes in harsh climates can cost significantly more. If the home you're considering has a roof that's 20 years old or an HVAC system that's at the end of its life, factor that into your budget now.
Planning for Today's Expenses, Not Tomorrow's
What does your life look like in three to five years? Are kids on the horizon? A career change? Aging parents who might need support? A home that fits today's budget might be tighter than expected if circumstances change. Build some cushion for a future you can't fully predict.
Ignoring the Lifestyle Cost of Stretching
Being house poor, owning a home that consumes so much of your income that you can't save, travel, go out, or handle surprises without stress, has a real quality-of-life cost. The home becomes a source of anxiety rather than stability. That's worth avoiding even if it means a smaller home or a less exciting neighborhood.
What If Your Number Is Lower Than You Hoped?
For many first-time buyers, especially in expensive markets, the honest affordability calculation produces a number that feels discouraging. What you can comfortably afford may be significantly less than what homes in your target area cost.
If that's your situation, a few things are worth exploring:
- Down payment assistance programs: These can reduce your loan amount and monthly payment significantly. Many first-time buyers don't know how much help is available to them.
- Different neighborhoods or property types: Condos, townhouses, or areas just outside your first-choice neighborhood may offer better value.
- House hacking: Buying a multi-family home and renting out a unit can make higher-priced properties financially workable by offsetting your mortgage with rental income.
- A longer savings runway: Sometimes the right answer is to wait, save more aggressively, pay down debt, and buy in a stronger financial position in one to two years.
None of these are consolation prizes. They're real strategies that many buyers have used successfully to get into homeownership in challenging markets.
Final Thoughts
The most important number in homebuying isn't what your lender will approve. It's what your life can actually sustain, comfortably, over the long term.
Take the time to do this math honestly, before you fall in love with a specific home or get anchored on a price range based on what others are spending. Know your real number. Search within it. And give yourself the financial breathing room to actually enjoy the home you buy.
A smaller home within a budget that works is a far better purchase than a larger home that keeps you up at night, wondering how you'll cover everything. The home you can afford is always the right one.
Sources & Further Reading
For authoritative information on the topics covered in this article, consult these resources:
