How Much House Can You Afford? Complete Guide

How how much house can you afford? complete guide works in practice

Home affordability is the maximum home price you can carry without straining your budget. Lenders use debt-to-income (DTI) ratios; you should also account for maintenance, emergencies, and lifestyle costs.

The goal is not to memorize every term — it is to know which inputs matter and what outcome you are aiming for.

So what: When you can explain this in your own words, you are far less likely to accept a bad quote, fee, or assumption.

A real scenario worth running

Household gross income $10,000/month, $500/month other debt, 20% down, 6.5% mortgage rate. Step by step: 28% housing cap = $10,000 × 0.28 = $2,800/month PITI → 36% total debt cap = $3,600 − $500 existing = $3,100 max housing → Binding limit = $2,800/month → supports ~$420k home with 20% down. Bottom line: Affordable home price ≈ $420,000 with $2,800/month total housing payment.

So what: Plug your own numbers into the same logic before you decide.

The 28/36 rule in detail

Mortgage lenders use two ratios to determine how much you can borrow:

Front-end ratio (28%): Total housing payment ÷ gross monthly income ≤ 28%

Back-end ratio (36%): All monthly debt payments ÷ gross monthly income ≤ 36%

Lenders approve the lower of what these ratios allow. Some programs (FHA, VA) allow higher ratios — but tighter ratios leave room for savings and emergencies.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

Worked example: income $8,000/month gross

If you pay $400/month on car and student loans:

• Back-end housing max = $2,880 − $400 = $2,480/month
• Front-end cap ($2,240) is binding — lender uses $2,240 for housing

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

What counts as housing cost

Include in your 28% calculation:

• Principal and interest (P&I from mortgage)
• Property taxes (monthly escrow amount)
• Homeowners insurance
• HOA/condo fees
• PMI (if down payment is under 20%)

Do NOT forget maintenance — budget 1% of home value per year on top of PITI. On a $400k home that's $333/month not counted by lenders but essential for affordability.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

DTI and loan types

Higher DTI approval ≠ wise spending. Leave margin for childcare, retirement, and emergencies.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

Down payment impact on affordability

$400,000 home, 6.5% rate, 30-year term:

Plus taxes/insurance ~$450/month in example markets.

20% down removes PMI and lowers P&I — often the difference between approved and comfortable.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

How much house can you actually afford?

Lender max ≠ your max. A safer personal rule:

On $120,000 gross income ($10,000/month):

• Conservative: $300,000 home
• Moderate: $360,000 home
• Lender might approve: $450,000+ — but leaves little margin

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

Beyond the ratios — personal affordability

Consider:

• Emergency fund (3–6 months expenses) intact after closing — not drained by down payment
• Retirement savings still on track (15%+ of income ideally)
• Childcare, healthcare, commuting — not in DTI but real costs
• Job stability — can you afford this payment if income drops?
• Future goals — travel, education, career change

Getting pre-approved for $500,000 doesn't mean spending $500,000 is wise.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

First-time buyer tips

1. Get pre-approved (not just pre-qualified) before house hunting
2. Compare at least 3 lender quotes — rates vary 0.25–0.5%
3. Budget 2–5% closing costs beyond down payment
4. Don't skip the home inspection
5. Keep $10,000–$20,000 buffer after closing for repairs and appliances

Use our home affordability calculator with your income, debts, and down payment — then stress-test at +1% interest rate.

So what: Run your own inputs before you commit — small changes in assumptions can shift the outcome sharply.

Common mistakes

1. 28% rule: housing costs ≤ 28% of gross monthly income — this quietly costs you over time.
2. 36% rule: all debt payments ≤ 36% of gross income — this quietly costs you over time.
3. Down payment size directly affects loan amount and PMI — this quietly costs you over time.
4. Pre-approval ≠ afford what you're comfortable paying — this quietly costs you over time.
5. Budget for 1–2% of home value annually in maintenance — this quietly costs you over time.

What to do next

Use our Home Affordability Calculator to model your situation — change one input at a time to see what moves the result most.