Does every month have a different payment?

The total scheduled payment stays the same on a fixed-rate loan. What changes is the split between principal and interest inside that fixed amount.

Why does the final payment look different?

Each month is rounded to whole cents, which can leave a tiny residual at the end. Servicers (and our calculator) adjust the final period so the balance lands on exactly $0.

How mortgage amortization works

Your mortgage payment is the same number every month, but the amount of it that pays off the loan vs. the amount that pays the bank changes every single month. That mechanic is amortization.

Interest is charged on what you still owe

Each month the lender charges interest on whatever balance you have at the start of that month — not on the original loan amount. The leftover part of your payment reduces principal.

monthly_interest = beginning_balance * (annual_rate / 12)
scheduled_principal = scheduled_payment - monthly_interest
ending_balance = beginning_balance - scheduled_principal

Why early payments are mostly interest

At the start, your beginning balance is the largest it will ever be. Multiplying that by the monthly rate produces a big interest charge, leaving relatively little left to put toward principal. As principal slowly drops, the interest charge drops with it, and more of each payment goes to principal. By the last few years, almost all of every payment is principal.

What a schedule shows

The interest charge for each month.
The principal portion of the scheduled payment.
Any extra principal you applied that month.
The new ending balance.
Cumulative interest and principal totals.

Why extra principal is so powerful

An extra principal payment doesn't just reduce your balance once. It also reduces every future month's interest charge, because the lender always charges interest on the new (lower) balance. That's why even small extras compound into years saved on the term.

Frequently asked

Does every month have a different payment?: The total scheduled payment stays the same on a fixed-rate loan. What changes is the split between principal and interest inside that fixed amount.
Why does the final payment look different?: Each month is rounded to whole cents, which can leave a tiny residual at the end. Servicers (and our calculator) adjust the final period so the balance lands on exactly $0.

Estimates only. This calculator is not a loan offer, loan approval, official Loan Estimate, Closing Disclosure, tax advice, legal advice, or financial advice. Actual payments, rates, taxes, insurance, mortgage insurance, closing costs, and loan terms may vary. Contact a qualified lender, tax professional, or financial advisor for guidance.