A lender will pre-approve you for more house than you can afford. That’s not a bug — it’s a feature of the system. Lenders care about whether you’ll repay, not whether you’ll have money left over for anything besides the mortgage.
In 2026, with average 30-year fixed rates around 6.5% and home prices still elevated from the post-pandemic run-up, the gap between “what a bank will lend you” and “what you can actually afford” is wider than it’s been in a decade.
This guide walks through the real math of home affordability — the 28/36 rule, down payment scenarios, PITI breakdowns, and the hidden costs most first-time buyers never see coming.
The 28/36 rule explained
Lenders use two ratios to determine how much house you can afford:
- Front-end ratio (28%): Your total monthly housing costs — principal, interest, taxes, and insurance (PITI) — should not exceed 28% of your gross monthly income.
- Back-end ratio (36%): Your total monthly debt payments — PITI plus car loans, student loans, credit card minimums, and other recurring debts — should not exceed 36% of your gross monthly income.
Example: You earn $90,000/year ($7,500/month gross).
| Ratio | Calculation | Maximum |
|---|---|---|
| Front-end (28%) | $7,500 × 0.28 | $2,100/month PITI |
| Back-end (36%) | $7,500 × 0.36 | $2,700/month total debt |
If you have $400/month in existing debt payments (car loan + student loan minimums), that leaves $2,300/month for PITI — but the front-end ratio caps you at $2,100. The tighter of the two ratios determines your actual budget.
How much house can you afford at different incomes?
Let’s use the 28% front-end ratio, a 6.5% 30-year fixed rate, 10% down payment, and estimated 1.2% annual property tax + 0.5% insurance.
| Annual Income | Max PITI | Max Home Price (10% down) | Monthly Payment |
|---|---|---|---|
| $60,000 | $1,400 | ~$175,000 | $1,400 |
| $75,000 | $1,750 | ~$225,000 | $1,750 |
| $90,000 | $2,100 | ~$275,000 | $2,100 |
| $110,000 | $2,567 | ~$340,000 | $2,567 |
| $130,000 | $3,033 | ~$405,000 | $3,033 |
| $150,000 | $3,500 | ~$470,000 | $3,500 |
These are maximums — not targets. Buying at the top of your pre-approval leaves no room for savings, maintenance, or lifestyle changes.
Down payment scenarios
The down payment dramatically affects your monthly payment and total interest. Here’s what different down payment sizes look like on a $300,000 home at 6.5%:
| Down Payment | Amount Down | Loan Amount | Monthly P&I | PMI | Total Monthly | Years to 20% Equity |
|---|---|---|---|---|---|---|
| 3% (FHA) | $9,000 | $291,000 | $1,839 | $217 | $2,056 | ~10 years |
| 5% (Conventional) | $15,000 | $285,000 | $1,801 | $142 | $1,943 | ~7 years |
| 10% | $30,000 | $270,000 | $1,706 | $95 | $1,801 | ~4 years |
| 15% | $45,000 | $255,000 | $1,611 | $48 | $1,659 | ~2 years |
| 20% | $60,000 | $240,000 | $1,516 | $0 | $1,516 | Day 1 |
The difference between 3% down and 20% down is $540/month — and no PMI. That’s $6,480/year. Over 5 years, the 20% down buyer saves $32,400 in payments plus the avoided PMI costs.
But saving 20% takes time. At $500/month saved, it takes 10 years to save $60,000 for a 20% down payment on a $300,000 home. During those 10 years, home prices may rise faster than your savings. The decision isn’t just financial — it’s strategic.
The PITI breakdown
Your monthly housing payment has four components. Here’s the breakdown on a $300,000 home with 10% down ($270,000 loan at 6.5%):
| Component | Monthly Cost | Annual Cost |
|---|---|---|
| Principal & Interest (P&I) | $1,706 | $20,472 |
| Property Taxes (1.2%) | $300 | $3,600 |
| Homeowners Insurance (0.5%) | $125 | $1,500 |
| PMI (until 20% equity) | $95 | $1,140 |
| Total PITI | $2,226 | $26,712 |
On a $90,000 salary ($7,500/month gross), PITI is $2,226/month — that’s 29.7% of gross income. Above the 28% guideline.
What most calculators don’t include:
| Hidden Cost | Monthly Estimate |
|---|---|
| Maintenance (1% of home value/year) | $250 |
| Utilities (water, gas, electric, trash) | $300 |
| HOA fees (if applicable) | $100–$500 |
| Home warranty (optional) | $50 |
| True monthly housing cost | $2,926+ |
That $2,226 PITI is really $2,926+ when you account for maintenance and utilities. On $7,500/month gross, that’s 39% — well above the 28% guideline.
Interest rate sensitivity
Mortgage rates change the affordability math dramatically. Here’s the monthly P&I on a $270,000 loan (10% down on $300K):
| Rate | Monthly P&I | Difference vs 6.5% | Annual Difference |
|---|---|---|---|
| 5.5% | $1,533 | -$173 | -$2,076 |
| 6.0% | $1,619 | -$87 | -$1,044 |
| 6.5% | $1,706 | $0 (baseline) | $0 |
| 7.0% | $1,796 | +$90 | +$1,080 |
| 7.5% | $1,888 | +$182 | +$2,184 |
| 8.0% | $1,981 | +$275 | +$3,300 |
A 1% rate change changes your monthly payment by ~$175 and your annual housing cost by ~$2,100. On a 30-year mortgage, that 1% difference costs or saves you $63,000 in interest over the life of the loan.
The strategic takeaway: If rates drop 1%+ from where you bought, refinancing is worth serious consideration. The break-even point on refi closing costs is usually 18–24 months at that spread.
The real budget
Here’s what a realistic budget looks like for a first-time buyer earning $90,000/year buying a $300,000 home with 10% down:
| Monthly Expense | Amount |
|---|---|
| Gross income | $7,500 |
| Federal tax (~18%) | -$1,350 |
| State tax (~5%) | -$375 |
| FICA (7.65%) | -$574 |
| Health insurance (employer plan) | -$400 |
| Net take-home pay | ~$4,801 |
| PITI + PMI | -$2,226 |
| Utilities | -$300 |
| Maintenance savings | -$250 |
| Groceries | -$500 |
| Transportation | -$400 |
| Minimum debt payments | -$300 |
| Remaining | ~$825 |
$825/month for everything else — dining, entertainment, travel, gifts, clothing, savings beyond maintenance, emergency fund, retirement. That’s tight.
If you’re saving 15% toward retirement ($1,125/month), the remaining drops to -$300. You’d be spending more than you earn.
This is the gap between pre-approval and affordability. The bank says you can afford the payment. The budget says you can’t afford your life.
First-time buyer programs
If the numbers look tight, you’re not alone. Here are programs that can help:
| Program | Benefit | Income Limit | Down Payment Requirement |
|---|---|---|---|
| FHA Loan | Lower credit requirement (580+), 3.5% down | None | 3.5% |
| Conventional 97 | 3% down, no PMI cancellation issues | Varies | 3% |
| USDA Loan | 0% down, lower rates | 115% of area median | 0% |
| VA Loan | 0% down, no PMI, flexible credit | None (must be veteran) | 0% |
| FHA 203(k) | Renovation + purchase in one loan | None | 3.5% |
FHA loans are the most common entry point for first-time buyers, but they require mortgage insurance for the life of the loan (unless you put 10%+ down, in which case PMI drops after 11 years). Conventional loans let you cancel PMI once you reach 20% equity.
Frequently asked questions
How much house can I afford on a $90,000 salary? With 10% down at 6.5%, roughly $275,000–$300,000 using the 28% front-end ratio. But your actual budget depends on your other debts, lifestyle costs, and savings goals. Many buyers at this income level find $250,000–$275,000 more comfortable.
What is the 28/36 rule for mortgages? Your monthly housing costs (PITI) should not exceed 28% of gross income, and your total debt payments (including housing) should not exceed 36%. These are maximums, not targets.
How much down payment do I need for a house in 2026? 3–5% minimum for FHA and conventional loans, but 20% eliminates PMI and lowers your monthly payment by $500+/month. A 10% down payment is a reasonable middle ground for many buyers.
Does PMI go away? On conventional loans, PMI automatically cancels when you reach 22% equity (or can be requested at 20%). On FHA loans with less than 10% down, PMI lasts the life of the loan. The only way to remove FHA PMI is to refinance into a conventional loan.
What’s included in PITI? Principal (loan balance reduction), Interest (cost of borrowing), Taxes (property tax), and Insurance (homeowners insurance). PMI is sometimes added as a fifth component.
How does my credit score affect my mortgage rate? Excellent credit (760+) gets the best rates, roughly 0.5–1.5% lower than fair credit (640–699). On a $300,000 loan, that’s $100–$300/month and $36,000–$108,000 over 30 years. Check your score at least 6 months before applying.
Should I buy a house or rent in 2026? Run the numbers. If you plan to stay 5+ years, buying usually wins in most markets. If you might move in 3 years or less, renting is almost always cheaper when you factor in transaction costs (6% agent commission on sale = $18,000 on a $300K home).
Calculate your exact affordable price range with our home affordability calculator. Adjust the down payment, rate, and debt levels — see exactly how much house fits your budget.
Before you start touring homes, run your debt-to-income ratio. A DTI above 43% will disqualify you from most conventional loans and make your rate significantly worse. Paying down existing debt is often the fastest path to a better mortgage.