The 28/36 rule is what lenders use to decide if you qualify. It's not the same as what you should actually spend. Here's the difference - and a quick check to see where you stand.
DTI quick check
car, student, credit cards
Front-end DTI
✓27.0%
limit: 28%
Back-end DTI
✓31.5%
limit: 36–43%
You qualify - but you're using most of your allowance.
Any income drop or new expense will put pressure on this payment.
Estimates only. Lender limits vary - some accept back-end DTI up to 50% with strong compensating factors.
28%
of gross monthly income
Covers housing costs only: principal, interest, property tax, homeowners insurance, and HOA fees. Nothing else counts in this ratio.
Example - $90k income
36–43%
of gross monthly income
Everything housing costs PLUS all other minimum monthly debt payments: car loans, student loans, credit card minimums, personal loans. Every recurring obligation counts.
Example - $90k inc + $600/mo debts
The 28/36 rule originated with Fannie Mae underwriting standards in the 1970s. It was designed as a conservative guideline for a different housing market - lower prices, lower rates, and smaller household debt loads than exist today. It became industry standard not because it's mathematically precise, but because it gave lenders a consistent benchmark.
In practice, most conventional lenders now accept back-end DTI up to 43–45%, and FHA loans allow up to 50% with compensating factors like strong credit or large reserves. Some lenders in high-cost markets regularly approve 47–50% back-end DTI. The "36" in 28/36 is a guideline - the real ceiling is higher. The 28% front-end limit is enforced more strictly.
What the rule doesn't account for
Cost of living. In San Francisco or New York, 35% housing-to-income is normal. In Omaha or Indianapolis, 20% is achievable. The rule is a national average applied uniformly - it doesn't know where you live.
This table shows the maximum monthly housing payment (front-end 28% and back-end 43% combined limit) for different income and debt combinations. Find your income row, then your debt column.
| Annual Income | $0 debt | $200/mo debt | $400/mo debt | $600/mo debt | $800/mo debt |
|---|---|---|---|---|---|
| $60k | $1,400 | $1,295 | $1,095 | $895 | $695 |
| $80k | $1,867 | $1,667 | $1,467 | $1,267 | $1,067 |
| $100k | $2,333 | $2,133 | $1,933 | $1,733 | $1,533 |
| $120k | $2,800 | $2,600 | $2,400 | $2,200 | $2,000 |
| $150k | $3,500 | $3,300 | $3,100 | $2,900 | $2,700 |
Based on 28% front-end and 43% back-end DTI limits. Binding limit shown - whichever is lower controls the result.
Green = front-end binding (debt is not the problem).
Amber = back-end binding (existing debt is limiting the budget).
These are the only real levers. Each one has a different cost, timeline, and impact on your maximum home price.
Every $100/month you eliminate from existing debts adds roughly $20,000 to your maximum home price. Pay off the highest-rate debt first - credit cards, then personal loans, then car.
A larger down payment means a smaller loan, which means a lower monthly payment, which improves front-end DTI. It also eliminates PMI at 20%, freeing up $150–$250/month.
The simplest fix. Every $50,000 less in home price reduces your monthly payment by roughly $300 at current rates. Not a consolation - it's what keeps you financially stable.
High-cost markets
San Francisco, NYC, Los Angeles, Seattle
Median home prices of $700k–$1.2M mean the 28% rule is aspirational for most buyers. Households routinely carry 35–42% front-end DTI in these markets. Lenders know this and often have regional flexibility. What saves buyers here: dual incomes, large down payments, and significantly higher salaries.
Affordable markets
Midwest, Southeast, smaller metros
Median prices of $200k–$350k make the 28% rule genuinely achievable on a $70k–$90k salary. In these markets, buyers who follow the rule closely often end up with real financial breathing room - a rarity in today's environment.
The rule is a national standard applied to local markets. Use it as a ceiling, not a target. In an expensive market, know you're stretching - and plan accordingly with larger reserves and stable income. In an affordable market, staying well under 28% is realistic and worth it.
Primary tool
Home Affordability Calculator
Enter income, debts, down payment, and rate. See your front-end and back-end DTI breakdown with your exact home price range.
The 28% front-end limit is the one to respect. Staying under it means your housing payment is genuinely manageable regardless of what else happens to your finances.
Existing debt is the hidden variable. Two people with the same income can have completely different affordable home prices based solely on their monthly debt obligations.
The rule comes from the 1970s. Lenders routinely approve higher. That's not permission to go higher - it's a reminder that qualifying and affording are two different things.
Estimates based on your inputs. Actual results may vary. Terms →