Compare monthly payments, total interest, and equity build-up side by side. See exactly how much you save — or lose — with each option.
⚡ Quick Answer: On a $300,000 loan — 15-year at 6.2%: $2,575/mo, total interest $163K. 30-year at 6.8%: $1,957/mo, total interest $404K. The 15-year saves $241,000 in total interest but costs $618 more per month. If you can afford the higher payment, 15-year almost always wins.
| Loan Amount | 15yr Monthly (6.2%) | 30yr Monthly (6.8%) | Interest Saved |
|---|---|---|---|
| $200,000 | $1,717/mo | $1,305/mo | ~$160K |
| $300,000 | $2,575/mo | $1,957/mo | ~$241K |
| $400,000 | $3,433/mo | $2,610/mo | ~$321K |
| $500,000 | $4,291/mo | $3,262/mo | ~$401K |
| $600,000 | $5,150/mo | $3,914/mo | ~$481K |
Two factors compound the savings: (1) Lower interest rate — 15-year mortgages typically carry rates 0.5–0.75% lower than 30-year, and (2) Half the repayment period — you pay interest for only 15 years instead of 30. Together, these two factors mean you pay roughly 40% of the total interest of a 30-year mortgage. On a $400K loan, the 15-year saves over $321,000 in interest alone.
Last updated: May 2026. Rates shown are averages for illustrative purposes — actual rates vary by lender, credit score, and loan type. Consult a licensed mortgage professional for your specific situation. Try our full Mortgage Calculator →