The Mortgage Ledger

United States

United States amortization calculator

A year-by-year breakdown of how each payment splits between interest and principal, and how the balance falls over time.

Your mortgage

Year-by-year breakdown

Total interest: $347,515 · Paid off August 2056

Early on, most of each payment is interest; the balance falls slowly at first, then faster. That's the shape of every amortizing mortgage.

YearPrincipalInterestBalance
1$3,684$17,900$296,316
2$3,911$17,673$292,405
3$4,152$17,431$288,252
4$4,409$17,175$283,844
5$4,681$16,903$279,163
6$4,969$16,615$274,194
7$5,276$16,308$268,918
8$5,601$15,983$263,317
9$5,947$15,637$257,371
10$6,313$15,270$251,057
11$6,703$14,881$244,354
12$7,116$14,468$237,238
13$7,555$14,029$229,683
14$8,021$13,563$221,662
15$8,516$13,068$213,147
16$9,041$12,543$204,106
17$9,599$11,985$194,507
18$10,191$11,393$184,316
19$10,819$10,765$173,497
20$11,486$10,097$162,011
21$12,195$9,389$149,816
22$12,947$8,637$136,869
23$13,746$7,838$123,123
24$14,593$6,990$108,530
25$15,494$6,090$93,036
26$16,449$5,135$76,587
27$17,464$4,120$59,124
28$18,541$3,043$40,583
29$19,684$1,899$20,898
30$20,898$685$0

An estimate for planning — not financial advice. Principal & interest only; property tax, insurance and any fees are separate.

Amortization is how your mortgage balance falls over time. Every payment is the same, but the split shifts: early on almost all of it is interest, and only slowly does more go to principal. This calculator shows the full schedule and the total interest you'll pay over the life of the loan.

How this calculator works

Each month, interest is charged on the remaining balance; whatever's left of your fixed payment reduces the principal. As the balance shrinks, the interest portion shrinks and the principal portion grows.

On a 30-year loan it takes years before more of each payment goes to principal than interest — which is why total interest can rival the amount borrowed.

The schedule shows that crossover point and the running balance, so you can see exactly how equity builds year by year.

A worked example

A $400,000 loan at a 6.5% example rate over 30 years — year one:

Monthly payment (P&I)
$2,528/mo
Interest paid in year 1
$25,868
Principal paid in year 1
$4,471
Total interest over 30 years
$510,178

In year one roughly 80% of your payments are interest — the principal share grows every year after.

Who it's for

  • You want to see where each payment actually goes.
  • You're curious how much total interest a loan costs.
  • You're planning extra payments and want to see the effect.

Frequently asked questions

What is an amortization schedule?

A month-by-month table showing how each mortgage payment splits between interest and principal, and the balance that remains after each one.

Why is so much of my early payment interest?

Interest is charged on the whole outstanding balance, which is largest at the start. As you pay the balance down, the interest portion of each payment falls.

How much total interest will I pay?

It depends on the rate and term — on a $400,000 loan at 6.5% over 30 years, total interest can approach the amount borrowed. See the example above.

How do extra payments change the schedule?

They go straight to principal, so they cut the balance early, reduce future interest, and shorten the loan. The overpayment calculator quantifies it.