Principal & interest vs. your actual mortgage bill
This calculator computes principal and interest (P&I) — the part of your mortgage that follows the amortization formula. What actually lands on your monthly statement is usually higher, because most servicers collect property tax, homeowners insurance, and sometimes PMI or HOA dues through an escrow account and bundle it into one payment, often called PITI (Principal, Interest, Taxes, Insurance). Add your local tax and insurance estimates on top of the P&I figure below for your real monthly cost.
Example: a $350,000 mortgage, 15-year fixed at 5.75%
A shorter term trades a higher monthly payment for dramatically less interest over the life of the loan:
| Item | Amount |
|---|---|
| Monthly payment (P&I) | $2,906.44 |
| Payment 1 — interest | $1,677.08 |
| Payment 1 — principal | $1,229.35 |
| Balance after payment 1 | $348,770.65 |
| Total interest over 15 years | $173,158.35 |
| Total paid | $523,158.35 |
| Payoff date | February 2041 |
Compare that to the same $300,000-range loan stretched to 30 years in the main amortization calculator's worked example, where total interest runs well over $380,000 — the shorter term more than pays for its higher monthly payment in interest saved.
Frequently asked questions
Does this include property tax, insurance, and PMI?
No. This calculates principal and interest (P&I) only, which is the part that follows the amortization formula. Your actual mortgage bill often also includes property tax, homeowners insurance, and possibly PMI or HOA dues bundled by your servicer into an escrow payment — together these are called PITI. Add those separately to P&I for your real total monthly housing payment.
How does a 15-year mortgage compare to a 30-year at the same rate?
A 15-year term has a higher monthly payment but pays off in half the time and with dramatically less total interest, because the balance shrinks faster and less time is spent accruing interest on a large balance. Run both terms through the calculator above with your own numbers to see the exact trade-off in dollars.
Should I make biweekly payments instead of monthly?
Paying half your monthly payment every two weeks results in 26 half-payments a year — the equivalent of 13 full monthly payments instead of 12. That extra payment is effectively an extra-principal strategy; approximate its effect here by dividing your annual extra amount by 12 and entering it as a monthly extra payment.
How do extra payments affect refinancing decisions?
The schedule's balance column tells you exactly how much equity you'd have at any point, which matters for refinancing since lenders base new terms on your current balance and the home's value. Extra payments accelerate that balance reduction, which can help you clear a PMI threshold or qualify for better refinance terms sooner.
What mortgage rate should I enter — the rate or the APR?
Enter your note rate (the interest rate on the promissory note), not the APR. The APR spreads closing costs and lender fees across the loan term and will always be slightly higher than the note rate; it is not the number used to compute your actual monthly principal-and-interest payment.