How Much House Can I Afford in 2026? The 28/36 Rule and Real Math
The shortest correct answer to "how much house can I afford?" is the 28/36 rule: keep your monthly housing payment under 28 percent of gross monthly income, and your total monthly debt payments under 36 percent. At 2026 mortgage rates near 6.5 to 7 percent, that math typically lets a household with $120,000 of gross annual income borrow about $325,000 to $400,000 in mortgage debt, supporting a home purchase around $400,000 to $500,000 depending on down payment and property tax rates. This guide walks through what each number means, why lenders will approve you for much more than you should actually borrow, and where 2026 mortgage market conditions sit.
The 28/36 Rule Explained
The 28/36 rule comes from decades of mortgage industry data on default risk. Two simple ratios:
- Front-end DTI (28 percent ceiling): total monthly housing payment (principal + interest + property tax + insurance + HOA + PMI, called PITI) divided by gross monthly income
- Back-end DTI (36 percent ceiling): front-end PITI plus all other monthly debt (auto loans, student loans, credit card minimums, child support, etc.) divided by gross monthly income
If your gross monthly income is $10,000, your housing payment should not exceed $2,800 and your total monthly debt payments should not exceed $3,600. That leaves about $400/month of headroom for non-housing debt.
What Your Monthly Housing Payment Actually Includes
PITI breakdown for a typical $400,000 home with 20 percent down at 6.75 percent (May 2026 average):
- Principal & interest (30-year fixed, $320,000 loan): $2,076
- Property tax (national average effective rate ~0.9% on $400k): $300
- Homeowners insurance (national average $1,900/yr): $158
- HOA (varies; assume single-family home, $0): $0
- Private mortgage insurance (PMI; not required with 20% down): $0
- Total PITI: $2,534/month
At a 28 percent front-end DTI cap, that monthly payment requires gross income of at least $2,534 / 0.28 = $9,050/month ($108,600/year).
Why Lenders Approve You for More Than You Should Borrow
Conventional underwriting guidelines (Fannie Mae, Freddie Mac) routinely approve back-end DTIs up to 45 percent with strong credit. FHA loans allow up to 50 percent in some cases. That is the lender's risk tolerance, not your finance-friendly target.
The gap between lender max and the 28/36 rule:
- Lender approves $720k home (45% DTI on $120k income)
- 28/36 rule supports about $475k home
The difference roughly $245k of extra mortgage corresponds to about $1,800/month of payment. Buying at the lender max means you have $1,800 less per month for retirement savings, college funds, vacations, and emergency reserves. Most financial planners consider 28/36 a guardrail; some hold even tighter (25/30 or 20/40).
Down Payment and Loan Type
The down payment changes the size of the loan and whether you owe PMI:
- Conventional loan, 20% down: no PMI. Lowest total monthly cost.
- Conventional loan, 3-19% down: PMI required, typically 0.5-1.5% of loan balance annually. Drops off automatically at 78% LTV (or 80% LTV by request).
- FHA loan, 3.5% down minimum: 1.75 percent upfront mortgage insurance premium (rolled into loan) plus 0.55 percent annual MIP. With less than 10% down, MIP is permanent. With 10%+ down, MIP drops off after 11 years.
- VA loan (eligible veterans/active duty): 0 percent down possible, no PMI. Funding fee 1.25-3.30 percent depending on use number and down payment, exempt for service-connected disability rating 10%+ or surviving spouses.
- USDA loan (rural eligible): 0 percent down. 1 percent upfront guarantee fee plus 0.35 percent annual fee.
Hidden cost: closing costs typically run 2 to 5 percent of the home price ($8,000 to $20,000 on a $400k home). Cash to close = down payment + closing costs. A 20 percent down payment on a $400k home requires $80,000 down plus $10,000 closing = $90,000 cash to close, often more than the down payment alone.
2026 Mortgage Rate Environment
30-year fixed conventional rates averaged 7.04 percent through 2025, with 2026 settling closer to 6.5 to 7.0 percent depending on Treasury yields and Fed posture. Each 0.5 percentage point change in rate moves the affordability math meaningfully:
| Rate | Monthly P&I on $320k loan | 30-year total interest |
|---|---|---|
| 6.0% | $1,919 | $370,800 |
| 6.5% | $2,022 | $408,000 |
| 7.0% | $2,129 | $446,400 |
| 7.5% | $2,237 | $485,400 |
| 8.0% | $2,348 | $525,300 |
A buyer who locked at 6.0 percent in early 2026 pays $429/month less than someone locking at 7.5 percent for the same loan, or about $5,150/year. Over 30 years, the rate difference is $114,600.
What Most Affordability Calculators Get Wrong
Three common omissions in online tools:
- State property tax variance: Texas effective rate ~1.81 percent vs Hawaii ~0.28 percent. A $400k home costs $7,240/year in property tax in Texas vs $1,120 in Hawaii, a $510/month difference that completely changes affordability math. The Home Affordability Calculator on FinanceToolz pulls per-state averages automatically.
- HOA and condo fees: a $250/month HOA on a $400k condo is the same as buying a $445k SFR without HOA in terms of monthly payment. Almost no one includes HOA in the affordability formula.
- True total cost of ownership: maintenance and repairs typically run 1 to 2 percent of home value per year ($4,000 to $8,000 on a $400k home), unpredictably. Major systems (roof, HVAC) need replacing every 15 to 25 years. None of this shows up in PITI but it's real money out the door.
How to Increase Your Affordability
- Pay down existing debt: every $300/month of debt freed up = $50k more borrowing capacity at a 6.75 percent rate.
- Improve credit score: going from 680 to 760+ FICO can drop your mortgage rate by 0.5 to 0.75 percentage points.
- Increase down payment: avoiding PMI saves about $200-$300/month on a $400k home. The dollar from PMI savings buys roughly $35-50k of additional home.
- Consider a longer term (40-year mortgages exist for non-QM): lower monthly payment but much more lifetime interest. Trade-off rarely worth it.
- Shop for lower property tax states: at the same income, a buyer in Colorado (~0.5% effective) can afford 20-30 percent more home than the same buyer in Illinois (~2.1% effective).
Solve for your own max affordable home price.
Open the Home Affordability CalculatorFrequently Asked Questions
What is the 28/36 rule?
A long-standing guideline that monthly housing payment should not exceed 28 percent of gross monthly income (front-end DTI) and total monthly debt should not exceed 36 percent (back-end DTI). Lenders may approve higher ratios but the 28/36 rule reflects what most planners consider a comfortable margin.
How much income do I need for a $400,000 house?
At 6.75 percent on a 30-year mortgage with 20 percent down ($320k loan), PITI is roughly $2,534/month including national-average property tax and insurance. Under the 28 percent front-end rule, that requires gross income of about $108,600. Higher property tax states (NJ, TX, IL) need more; lower property tax states (CO, HI, AL) need less.
What is PITI?
Principal, Interest, Taxes, and Insurance, the four components of a typical monthly mortgage payment. Some lenders include the "A" (HOA) for PITIA. PMI is added if down payment is less than 20 percent.
Should I buy at the lender-approved maximum?
Most planners say no. Lenders evaluate default risk; they don't evaluate whether you'll still have money for retirement savings, college funds, vacations, or emergencies. Buying at lender max means committing 45 percent of gross income to housing-related debt, which leaves little for everything else.
What are typical closing costs?
Two to five percent of the home price for conventional purchases. On a $400k home, expect $8,000 to $20,000. Costs include lender fees (origination, underwriting), third-party (title insurance, appraisal, recording), and prepaid items (12 months homeowners insurance, 2 months tax escrow). FHA, VA, and USDA loans add upfront mortgage insurance or funding fees on top.
How much should I put down?
20 percent avoids PMI and gives lowest total monthly cost. 3-5 percent gets you into the home faster but adds PMI ($150-300/month on a $400k loan) until you reach 78 percent LTV. The right answer depends on opportunity cost: extra dollars not used for down payment can sometimes earn more invested than the PMI they save.
Does mortgage rate matter more than home price?
For monthly payment, yes. A 1 percentage point rate increase costs roughly $230/month on a $350k loan, the same as a $34,000 higher home price at a fixed rate. Buyers in high-rate environments should aggressively shop lenders and consider rate buydowns, points, and seller credits.