A $300,000 mortgage at 6% for 15 years has a monthly payment of $2,532 for principal and interest. Over the full term you pay $455,683, of which $155,683 is interest. That is 52 cents of interest for every dollar borrowed.
In the first year you pay $30,379. $17,654 of that is interest and $12,725 goes toward principal, so 58% of your first year’s payments goes to interest. After year 1 the balance is $287,275.
The payment stays the same, but its mix shifts every month. Principal first exceeds interest in year 4 of 15.
With a 10-year term instead, the payment would rise to $3,331 but total interest would drop to $99,674, which is $56,009 less.
A rate half a point lower, 5.5%, gives a payment of $2,451, which is $80 less each month. A rate half a point higher, 6.5%, gives $2,613.
Adding $300 a month to the payment pays the mortgage off 2 years 4 months early and saves $27,346 in interest. Property taxes, homeowners insurance and mortgage insurance are not included in these figures.
Change these numbers in the mortgage calculator
Illustration only, not investment, tax or legal advice.
The numbers behind it
- Mortgage amount
- $300,000
- Interest rate (per year)
- 6%
- Term
- 15 years (180 months)
- Monthly payment
- $2,532
- Total interest
- $155,683
- Total paid
- $455,683
| Year | Payments | Interest | Principal | Balance at year end |
|---|---|---|---|---|
| 1 | $30,379 | $17,654 | $12,725 | $287,275 |
| 2 | $30,379 | $16,869 | $13,510 | $273,765 |
| 3 | $30,379 | $16,036 | $14,343 | $259,422 |
| 4 | $30,379 | $15,151 | $15,228 | $244,194 |
| 5 | $30,379 | $14,212 | $16,167 | $228,027 |
| 6 | $30,379 | $13,215 | $17,164 | $210,863 |
| 7 | $30,379 | $12,156 | $18,223 | $192,640 |
| 8 | $30,379 | $11,032 | $19,347 | $173,294 |
| 9 | $30,379 | $9,839 | $20,540 | $152,754 |
| 10 | $30,379 | $8,572 | $21,807 | $130,947 |
| 11 | $30,379 | $7,227 | $23,152 | $107,795 |
| 12 | $30,379 | $5,799 | $24,580 | $83,215 |
| 13 | $30,379 | $4,283 | $26,096 | $57,119 |
| 14 | $30,379 | $2,674 | $27,705 | $29,414 |
| 15 | $30,379 | $965 | $29,414 | $0 |
Sources and method
The standard reducing-balance loan formula: each month’s interest is charged on the balance still left, and the payment stays the same.
No outside data is used. The numbers you type in are the only inputs.
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