What Makes Up a Mortgage Payment?
When you take out a home loan, your monthly payment is more than just repaying what you borrowed. Lenders bundle multiple costs into a single monthly payment known as PITI:
- P — Principal: The actual loan amount you are repaying. Each month, a portion of your payment reduces the outstanding balance.
- I — Interest: The cost the lender charges for borrowing the money. In the early years of the mortgage, most of your payment goes toward interest rather than principal.
- T — Taxes: Property taxes assessed by your local government. The lender typically collects these monthly and pays them on your behalf through an escrow account.
- I — Insurance: Homeowner’s insurance (required by lenders) plus Private Mortgage Insurance (PMI) if your down payment is less than 20%.
Some lenders also include HOA fees and flood insurance in the monthly escrow payment.
Use our Mortgage Calculator to see exactly how all four components add up for your specific loan.
How Mortgage Payments Are Calculated
The standard mortgage payment formula (for principal and interest only) is:
M = P × [ r(1+r)^n ] / [ (1+r)^n − 1 ]
Where:
- M = Monthly payment
- P = Loan principal (purchase price minus down payment)
- r = Monthly interest rate (annual rate ÷ 12)
- n = Total number of payments (loan term in years × 12)
Example: A $300,000 home loan at 6.5% interest for 30 years:
- Monthly principal & interest payment = $1,896
- With 1.2% property tax ($300/month) and $100/month insurance: $2,296 total
- Over 30 years, total payments = $826,560 — of which $526,560 is interest
The Power of Extra Principal Payments
Making extra payments toward your principal is one of the most powerful ways to save money on a mortgage:
| Extra Payment | 30-Year $300K Loan at 6.5% | Interest Saved | Years Saved |
|---|---|---|---|
| None | $1,896/month | $0 | 0 |
| $100/month extra | $1,996/month | $52,700 | 4.5 years |
| $200/month extra | $2,096/month | $86,400 | 7.2 years |
| One extra payment/year | Equivalent to 13 payments/year | $65,200 | 5.3 years |
Even small extra payments compound dramatically because they permanently reduce the principal on which future interest is calculated. Our calculator’s Extra Payments tab shows you exactly how much time and money you will save.
Commercial vs. Residential Mortgages
Commercial mortgages work differently from home loans:
- Shorter Terms — Commercial loans often have 5, 7, or 10-year terms with longer amortization periods (20–25 years). This creates a balloon payment at the end — the remaining balance must be paid off or refinanced.
- Higher Rates — Commercial rates are typically 1–3% higher than residential rates.
- Stricter Qualification — Lenders evaluate the property’s income potential (debt service coverage ratio) rather than just your personal income.
Reverse Mortgages: How They Work
A reverse mortgage (HECM — Home Equity Conversion Mortgage) allows homeowners aged 62+ to convert home equity into cash without selling the home or making monthly mortgage payments:
- Eligibility: Youngest borrower must be 62+, home must be primary residence
- Loan Amount: Based on age, current interest rates, and home value (subject to FHA limits)
- Repayment: No monthly payments required. The loan is repaid when the last borrower sells the home, moves out permanently, or passes away.
- Key Risk: Interest accrues over time, reducing the equity left for heirs. Borrowers must still pay property taxes and insurance.
How Much House Can You Afford?
Lenders use two key ratios to determine your maximum loan amount:
- Front-End Ratio: Your total monthly housing payment (PITI) should not exceed 28% of your gross monthly income.
- Back-End Ratio: Your total monthly debt (housing + credit cards + car loans + student loans) should not exceed 36% of gross income.
Example: If your household earns $8,000/month gross, your maximum housing payment is $2,240 (28%) and your total debt payments should stay under $2,880 (36%).
Our calculator’s Affordability tab lets you test different income, debt, and down payment scenarios.
Property Tax Considerations by State
Property taxes vary dramatically by location:
- High-tax states: Texas (1.6–2.0% of home value), New Jersey (1.8–2.4%), Illinois (1.7–2.2%)
- Low-tax states: Hawaii (0.27%), Alabama (0.40%), Colorado (0.51%)
- Homestead Exemptions: Many states reduce taxable value for primary residences. Texas exempts up to $100,000 from school district taxes for qualified homeowners.
Always factor local property tax rates into your affordability calculation — they can add several hundred dollars to your monthly payment.
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