Mortgage Calculator · Practical guide
15-Year vs. 30-Year Mortgage
The 15-year costs about 38% more each month but cuts total interest by more than half.
At a glance
The Short Answer
On a $320,000 loan at 6.5%, a 30-year mortgage costs $2,022.62 per month and $408,142 in total interest, while a 15-year mortgage costs $2,787.54 per month and only $181,758 in interest. Choosing 15 years raises the payment 38% but saves $226,385 in interest.
Interactive tool
Mortgage Calculator
Enter your own values, then compare the result with the examples below.
Mortgage Summary
| Year | Interest | Principal | Balance |
|---|
| Month | Interest | Principal | Balance |
|---|
Side-by-Side Comparison
| 15-Year at 6.5% | 30-Year at 6.5% | |
|---|---|---|
| Monthly payment (P&I) | $2,787.54 | $2,022.62 |
| Number of payments | 180 | 360 |
| Total paid | $501,758 | $728,142 |
| Total interest | $181,758 | $408,142 |
Monthly Payment per $100,000 Borrowed
Scale these figures to your own loan amount:
| Interest Rate | 15-Year Term | 30-Year Term |
|---|---|---|
| 5% | $790.79 | $536.82 |
| 6% | $843.86 | $599.55 |
| 7% | $898.83 | $665.30 |
Which Term Fits You?
Choose 15 years if the higher payment fits comfortably in your budget and you want to build equity fast — 15-year loans also typically carry rates about half a point lower than 30-year loans, widening the savings. Choose 30 years if you value cash-flow flexibility; you can always pay extra toward principal to mimic a shorter term while keeping the option to fall back to the lower required payment.
Frequently Asked Questions
Are 15-year mortgage rates lower than 30-year rates?
Usually yes, often by 0.25 to 0.75 percentage points, because lenders take less risk over the shorter period. That rate gap increases the interest savings even further.
Can I pay a 30-year mortgage like a 15-year one?
Yes — paying the 15-year amount each month on a 30-year loan pays it off in roughly 15 years, with a slightly higher interest cost if your rate is higher. Confirm there is no prepayment penalty.
How much income do I need for a 15-year mortgage?
Lenders generally cap housing costs near 28% of gross income. A $2,788 payment implies roughly $10,000 per month of gross income, before counting taxes, insurance, and other debts.
Is a 20-year mortgage a good compromise?
It can be. On $320,000 at 6.5%, a 20-year term costs $2,385.83 per month with about $252,600 in total interest — roughly midway between the 15- and 30-year options.