How Much House Can I Afford? (The Real Math, Not the Bank's Math)

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Here's a fun experiment: go to any mortgage lender's website and see how much they'll approve you for. Now take that number and multiply it by 0.7. That's closer to what you can actually afford without becoming "house poor" - owning a nice home but having no money for anything else.

Banks calculate what you can pay. This guide helps you figure out what you should pay. There's a massive difference, and getting it right is the single biggest financial decision most people will ever make.

The Rules of Thumb (And Why They're Just Starting Points)

You've probably heard the standard advice. Here's what each rule says, and when it breaks down.

These rules were created when interest rates were lower, student loan debt barely existed, and a single income could support a household. They're still useful starting points, but your real number depends on your complete financial picture.

The Real Math: What Can You Actually Afford?

Forget the rules of thumb for a minute. Here's how to calculate your actual number.

1. Start with your monthly take-home pay - Not gross, not pre-tax. The actual money that hits your bank account after taxes, 401(k), and health insurance.
2. Subtract your non-housing essentials - Car payment, insurance, student loans, groceries, utilities, phone, childcare. Be honest, not optimistic.
3. Subtract what you want to save and invest - At least 10-15% of gross income toward retirement and savings. Don't sacrifice your future for a house.
4. Subtract what you want for life - Dining out, hobbies, travel, entertainment. Skip this and you'll be miserable in your new home.
5. What's left is your real housing budget - This is your maximum monthly payment including principal, interest, taxes, insurance, and PMI.

Use our rent vs. buy calculator to compare the true cost of buying at different price points versus what you're paying in rent now.

The Costs Everyone Forgets

Your mortgage payment is just the beginning. The real cost of homeownership includes a bunch of expenses that don't show up in the lender's calculator. We've got a full breakdown of hidden homeownership costs, but here's the quick version:

That maintenance number isn't optional. Roofs need replacing ($8,000-$15,000), HVAC systems die ($5,000-$10,000), and plumbing breaks at the worst possible time. Budget for it or be surprised by it - those are your only two options.

How Much Do You Need Saved Before Buying?

The down payment is the obvious one, but it's not the only cash you need. Here's the full savings checklist:

• Down payment (3.5-20%) - FHA loans require as little as 3.5%. Conventional loans start at 3-5%. But putting less than 20% down means paying PMI, which adds $100-$300/month. Our FHA loans guide covers the tradeoffs.
• Closing costs (2-5%) - On a $300,000 home, that's $6,000-$15,000. These include appraisal, inspection, title insurance, attorney fees, and lender origination fees. Sometimes negotiable, rarely avoidable.
• Emergency fund (3-6 months) - Including your new, higher housing payment. Buying a house without an emergency fund is a recipe for credit card debt the first time something breaks.
• Moving and setup costs ($3,000-$10,000) - Moving company, new furniture, appliances, immediate repairs, window treatments, lawn equipment. It adds up fast.

That number is why our first-time home buyer budgeting guide recommends starting to save 2-3 years before you plan to buy.

When the Bank Says Yes But Your Budget Says No

Mortgage lenders will routinely approve you for 4-5x your income. A household earning $100,000 might get approved for $400,000-$500,000. At 6.5% with 10% down, a $450,000 home means a monthly payment around $3,200 - before property taxes and insurance push it past $4,000.

On $100,000 gross ($6,500/month take-home), a $4,000+ housing payment is 62% of take-home pay. That leaves almost nothing for savings, retirement, or having a life. The bank says you can afford it because their risk models say you probably won't default. They don't care whether you'll be stressed, unable to save, or eating ramen every night.

The sweet spot for most people: keep total housing costs (mortgage + taxes + insurance + maintenance) under 30-35% of take-home pay. That leaves room for everything else without feeling squeezed.

Special Programs That Expand Your Budget

If the numbers feel tight, there are legitimate programs that can help first-time buyers:

• FHA loans - 3.5% down with a 580+ credit score. Read our FHA loans guide.
• VA loans - $0 down for veterans and service members. See our VA home loans guide.
• USDA loans - $0 down in eligible rural and suburban areas. Check our USDA loans guide.
• Down payment assistance - Many states and cities offer grants or low-interest loans for first-time buyers. Search your state's housing finance agency.

And if you're still deciding whether buying makes sense at all, our renting vs. buying breakdown walks through when renting actually wins financially.