Why is most of my early payment interest?

Because interest is charged on the balance, and the balance is largest at the start. On a $320,000 loan at 6.5% over 30 years, the first month costs $1,733 of interest against a $2,023 payment — 86% — so only $289 goes to principal. The following months are nearly the same, which is why progress feels slow.

When does the principal part overtake the interest part?

On that same loan, at month 233 — year 19 of 30. Extra payments pull that crossover forward sharply: $200 a month more ends the loan in 280 months and saves $105,430 of interest, which also means the flip arrives far earlier than it would otherwise.

Does the schedule include property tax and insurance?

No. An amortization table covers principal and interest only. Property tax, homeowners insurance and, above 80% loan-to-value, private mortgage insurance all sit outside the table even though they appear on your monthly statement.

Will my real amortization match the table exactly?

Close, not to the penny. Payment timing, rounding to cents and the annual escrow analysis all nudge the figures. The principal-and-interest split is arithmetic, so the shape of the curve holds; treat the table as a map rather than a receipt.

What Is an Amortization Schedule and How to Read It?

Q: What is an amortization schedule?

A month-by-month table of a loan: the balance at the start of each payment, the payment itself, how much of it is interest, how much reduces principal, and the balance left after. Fixed-rate mortgages have a schedule that can be printed in advance because nothing in it depends on the future.

4 min read · updated October 7, 2026

A mortgage payment is the rare bill that never changes. The catch is that what the payment buys changes every single month, and the record of those changes is the amortization schedule.

It is one of the few documents in a home purchase that is pure arithmetic — no underwriting, no negotiation — so once you can read it, several arguments about mortgages simply stop being confusing. Everything below is on one loan: a $320,000 balance at 6.5% over 30 years, which the Amortization Calculatoron this site prices in a few seconds.

What the table actually contains

Each row is one payment: the balance you began the month with, the payment itself, how much of it was interest, how much went to principal, and the balance you ended with. Only the size of the payment is fixed by contract; the split inside it is decided by arithmetic, month by month, for thirty years. The calculator shows the yearly version of this table along with the payoff date, which is easier to read than 360 individual rows.

Why interest dominates the early years

Interest is nothing mysterious: it is the balance multiplied by the monthly rate. On this loan that is $1,733 in the first month out of a $2,023 payment — 86% of it — leaving just $289 for principal. Because the balance has barely moved, next month's interest is nearly the same. The first year pays about $20,700 of interest and retires roughly $3,600 of the debt. Compare that with the final twelve months, which pay $833 of interest in total.

The crossover, and how far away it is

Follow the two columns and you eventually reach the month when the principal part overtakes the interest part. On this loan that is month 233 — year 19. Until then, most of every payment is the cost of borrowing money you already used. It is why the balance barely budges early on: five years in, $320,000 has become $299,555, and after ten years it is still $271,284. Buyers who move in year four often feel cheated; the loan did not misbehave, it was simply early. The same mechanic is what makes a shorter term so much cheaper, which is the subject of 15-year versus 30-year mortgage.

The three lines worth reading

First, the closing balance on the date you actually expect to sell. That is what you will owe, not the price on the listing. Second, the total-interest figure, which is the real price of the borrowing: $408,142 here, against a $320,000 loan. Third, what the table becomes once you add an extra payment. Send an additional $200 a month and the loan ends in 280 months instead of 360, with interest falling to $302,713 — $105,430 saved (Mortgage Payoff Calculator frames the same arithmetic as a payoff date).

What the schedule leaves out

The table is principal and interest only. Your statement is bigger: property tax and homeowners insurance ride along in escrow (Property Tax Calculator), and above 80% loan-to-value, private mortgage insurance sits on every row until it can be cancelled (PMI Calculator). The table also assumes nobody touches the loan. Make a lump-sum payment and a recast rewrites the entire schedule, because a smaller balance is re-spread across the same remaining years (Recast Calculator).

Why your real numbers drift a little

Expect a few dollars of difference between the printed table and your statement. Payments land a day early or late, servicers round to cents, and escrow is reanalysed once a year. The principal-and-interest split itself is arithmetic, so the shape holds even where the pennies do not.

How to use it before you sign

Run the table and look at the balance on your expected move date rather than only at the payment. Run it again with an extra payment and decide whether the interest saved is worth that cash every month. Then run it at the rate your credit score actually gets you, because a half-point difference rewrites every row — the Mortgage Payment Calculator and the six levers for reducing a payment are the natural next clicks once the schedule stops being a mystery.