The fine print
What’s really in your monthly mortgage payment?
A mortgage payment is rarely just the loan. It’s a bundle — principal, interest, property tax, homeowners insurance, and often PMI and HOA — and the bundle is what you’ll actually owe every month for decades. Whether you’re buying your first home, downsizing in midlife, or re-entering the market after divorce, knowing each piece lets you compare loans honestly and avoid a payment that looks fine on paper but strains your real life.
Principal & interest — the amortization math
The core of the payment is calculated with the standard amortization formula. Each month you pay one flat amount; early on, almost all of it is interest, and as the balance shrinks more of each payment chips away at principal. The calculator above applies that formula directly to your loan amount, rate, and term.
- A longer term lowers the monthly payment but raises total interest dramatically — on a $320,000 loan at 6.625%, 30 years costs tens of thousands more in interest than 15.
- A lower rate shrinks both the monthly payment and total interest. Even a 0.5% difference compounds over 30 years.
- Putting more down reduces the principal, which reduces both the monthly P&I and (above 20%) eliminates PMI entirely.
PMI — the penalty for a smaller down payment
If your down payment is under 20% of the price, lenders usually require Private Mortgage Insurance — typically 0.5–1% of the loan amount per year. This calculator uses a midpoint of 0.75%. PMI protects the lender, not you, but it’s not permanent: it generally cancels automatically once your loan-to-value ratio reaches 80%, and you can request removal earlier in some cases.
Tax, insurance, and HOA — the costs people forget
Property tax and homeowners insurance are usually collected with your mortgage payment into an escrow account, so they feel like part of the loan even though they aren’t. Tax rates vary widely by county — the 1.1% default here is a rough national average; check your local rate. HOA only applies in communities with an association, but when it applies it can add hundreds a month.
Keep going
Wondering how much house you can afford in the first place? Our Home Affordability Calculator works backward from your income to the price you can carry. A Rent vs. Buy guide is also on the way to help you decide whether buying makes sense right now.
The caveat
This is an estimate only, not a loan offer or commitment to lend. Actual rates, taxes, insurance, and PMI vary by lender, credit profile, loan type, and location — and the default rate shown is a reasonable recent ballpark, not a guaranteed or live lender quote. For numbers tied to your real situation, consult a licensed lender or financial advisor. Educational estimates, not financial advice.