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How mortgage payments work

A monthly mortgage payment is usually called PITI: Principal, Interest, Taxes, and Insurance. Understanding how those pieces fit together makes every number on this site make sense.

Principal and interest

The loan itself is repaid through amortization. Each month, interest is charged on the outstanding balance, and whatever is left of your payment reduces the principal. Because the balance is highest at the start, early payments are mostly interest — the split shifts toward principal over time.

Monthly P&I = P · r(1 + r)^n / ((1 + r)^n − 1)
  P = loan amount   r = monthly rate (annual ÷ 12)   n = number of payments

Taxes and insurance

Property taxes and homeowners insurance are typically collected monthly into an escrow account and paid on your behalf. Property tax is a percentage of your home's value and varies widely by state and county; insurance depends on the home and coverage.

PMI

If your down payment is under 20%, conventional lenders add private mortgage insurance until your loan-to-value reaches 78–80%. It protects the lender, and you can have it removed as you build equity.

Try it

Estimate your own payment below — it updates as you type:

Authoritative resources

For consumer-focused, unbiased explanations of mortgages, see the U.S. Consumer Financial Protection Bureau (CFPB) and Freddie Mac's My Home. This calculator is for education and estimates only — not financial advice.