Buying a home is likely the biggest financial decision you'll ever make. Get it right, and you'll build wealth while enjoying a comfortable lifestyle. Get it wrong, and you could find yourself struggling to make payments, sacrificing your savings goals, or worse—facing foreclosure.
The question "how much house can I afford?" seems simple, but the answer depends on far more than just your income. Your debts, down payment, credit score, local property taxes, and even your lifestyle goals all play crucial roles in determining your true home affordability.
Let's break down exactly how to calculate what you can realistically afford—and help you avoid the costly mistake of buying more house than your budget can handle.
The 28/36 Rule: Your Starting Point
Most financial experts and mortgage lenders use the 28/36 rule as a baseline for home affordability:
- 28% Rule: Your monthly housing costs (mortgage principal, interest, taxes, and insurance—known as PITI) shouldn't exceed 28% of your gross monthly income.
- 36% Rule: Your total monthly debt payments (housing costs plus car loans, student loans, credit cards, etc.) shouldn't exceed 36% of your gross monthly income.
Real-World Example
Let's say you earn $85,000 per year, which equals roughly $7,083 in gross monthly income.
Using the 28/36 rule:
- Maximum housing payment: $7,083 × 0.28 = $1,983/month
- Maximum total debt: $7,083 × 0.36 = $2,550/month
If you're already paying $400/month toward a car loan and $200/month toward student loans, your available budget for housing drops to $1,950/month ($2,550 - $600).
What Lenders Actually Look At
While the 28/36 rule provides a helpful framework, mortgage lenders dig deeper into your financial picture. Here's what they evaluate:
Debt-to-Income Ratio (DTI)
Your DTI ratio is the single most important factor in mortgage approval. Lenders calculate two types:
- Front-end DTI: Housing costs divided by gross income (the 28% rule)
- Back-end DTI: All monthly debt payments divided by gross income (the 36% rule)
Many lenders will approve loans with back-end DTIs up to 43%, and some government-backed loans allow even higher ratios. However, just because you can qualify doesn't mean you should borrow that much.
Credit Score Impact
Your credit score directly affects your interest rate, which dramatically impacts affordability:
| Credit Score Range | Estimated APR* | Monthly Payment on $350,000 Loan | Total Interest Paid (30 years) | |-------------------|----------------|----------------------------------|-------------------------------| | 760-850 | 6.5% | $2,212 | $446,320 | | 700-759 | 6.8% | $2,282 | $471,520 | | 680-699 | 7.0% | $2,329 | $488,440 | | 660-679 | 7.2% | $2,376 | $505,360 | | 620-659 | 7.8% | $2,518 | $556,480 |
*Rates are illustrative examples based on typical market conditions
As you can see, a buyer with a 760+ credit score pays $306 less per month than someone with a 620 score—that's $3,672 per year and over $110,000 in savings over the life of the loan.
Down Payment Considerations
Your down payment affects affordability in multiple ways:
- 20% down: Avoids private mortgage insurance (PMI), which typically costs 0.5-1% of the loan amount annually
- 10% down: Requires PMI but keeps more cash available for emergencies
- 3-3.5% down: Available through FHA and some conventional loans, but increases monthly payments and total interest paid
For a $400,000 home:
- 20% down ($80,000) = $320,000 loan, no PMI
- 10% down ($40,000) = $360,000 loan + approximately $150-300/month PMI
- 3.5% down ($14,000) = $386,000 loan + approximately $160-320/month PMI
The Hidden Costs of Homeownership
Your mortgage payment is just the beginning. Smart buyers factor in these additional expenses:
Property Taxes
Property taxes vary wildly by location. In New Jersey, the average effective rate is 2.23%, meaning a $400,000 home costs $8,920/year in property taxes alone. In Hawaii, that same home would only cost $1,120/year at a 0.28% rate.
Homeowners Insurance
Expect to pay between $1,200 and $3,000+ annually, depending on your location, home value, and coverage level. Homes in hurricane or wildfire zones often cost significantly more to insure.
Maintenance and Repairs
The general rule is to budget 1-2% of your home's value annually for maintenance. For a $400,000 home, that's $4,000-$8,000 per year, or $333-$667 per month.
HOA Fees
If you're buying in a community with a homeowners association, monthly fees can range from $100 to $500+ depending on amenities and services included.
Utilities
Larger homes cost more to heat, cool, and maintain. Budget based on square footage and your local climate.
How to Calculate Your True Affordability
Here's a step-by-step approach to finding your real number:
Step 1: Calculate Your Monthly Income
Add up all reliable, documentable income sources:
- Gross salary/wages
- Bonus income (if consistent for 2+ years)
- Self-employment income (averaged over 2 years)
- Rental income
- Investment income
Step 2: List All Monthly Debts
Include minimum payments for:
- Auto loans
- Student loans
- Credit cards
- Personal loans
- Child support/alimony
- Any other recurring debt obligations
Step 3: Determine Your Comfortable Housing Budget
Rather than stretching to the maximum 28%, consider what percentage actually fits your lifestyle:
- 20-25% of gross income: Comfortable range that leaves room for savings and lifestyle
- 25-28% of gross income: Moderate stretch, requires careful budgeting
- 28-33% of gross income: Tight budget, limited flexibility for unexpected expenses
Step 4: Factor in All Housing Costs
Remember, your housing budget must cover:
- Mortgage principal and interest
- Property taxes
- Homeowners insurance
- PMI (if applicable)
- HOA fees (if applicable)
Step 5: Work Backward to Find Your Price Range
Once you know your comfortable monthly payment, you can calculate the home price you can afford.
Try the CashWise Home Affordability Calculator to input your specific numbers and get an instant estimate based on your income, debts, down payment, and local factors.
What Banks Will Approve vs. What You Should Spend
Here's a truth many homebuyers learn too late: mortgage lenders don't consider your savings goals, retirement contributions, childcare costs, or lifestyle preferences when approving your loan.
A bank might approve you for a $450,000 mortgage, but that doesn't mean buying a $450,000 home is smart for your situation.
Consider this example:
The Johnsons earn $120,000 combined and were approved for a $480,000 home. Instead, they bought a $380,000 home. The $400/month difference allowed them to:
- Max out their 401(k) contributions
- Build a six-month emergency fund in two years
- Take annual family vacations without guilt
- Avoid financial stress when one spouse changed careers
Tips for Improving Your Home Affordability
If the calculator shows you can afford less than you hoped, here are strategies to improve your situation:
Short-Term Strategies (1-6 months)
- Pay down credit card balances to lower your DTI
- Avoid opening new credit accounts
- Save aggressively for a larger down payment
Medium-Term Strategies (6-12 months)
- Pay off a car loan or consolidate debt
- Build credit score by maintaining perfect payment history
- Research down payment assistance programs in your state
Long-Term Strategies (1-2 years)
- Focus on income growth through promotions or side income
- Eliminate student loan or other significant debt
- Consider relocating to an area with lower home prices and property taxes
Find Your Number Today
Understanding how much house you can afford isn't just about getting approved for a mortgage—it's about setting yourself up for long-term financial success and avoiding the stress of being "house poor."
The best approach combines the mathematical rules (like the 28/36 guideline) with an honest assessment of your lifestyle, goals, and risk tolerance.
Ready to find your personalized home affordability number? Use the CashWise Home Affordability Calculator to input your income, debts, down payment, and location. In less than two minutes, you'll have a clear picture of your comfortable price range—so you can shop with confidence and avoid the trap of overspending on your biggest purchase.
Your future self will thank you for taking the time to get this calculation right.