The short answer: at a 6.5% rate, a $800,000 30-year fixed mortgage costs $5,056.54 a month in principal and interest; at 7%, $5,322.42. On a 15-year term at 6.5% the payment is $6,968.86. Taxes, insurance, HOA and mortgage insurance (if you put less than 20% down) come on top — open this loan in the full calculator to add them and see the complete amortization schedule.
| Rate | 30-year | 20-year | 15-year |
|---|---|---|---|
| 5.00% | $4,294.57 | $5,279.65 | $6,326.35 |
| 5.25% | $4,417.63 | $5,390.75 | $6,431.02 |
| 5.50% | $4,542.31 | $5,503.10 | $6,536.67 |
| 5.75% | $4,668.58 | $5,616.67 | $6,643.28 |
| 6.00% | $4,796.40 | $5,731.45 | $6,750.85 |
| 6.25% | $4,925.74 | $5,847.43 | $6,859.38 |
| 6.50% | $5,056.54 | $5,964.59 | $6,968.86 |
| 6.75% | $5,188.78 | $6,082.91 | $7,079.28 |
| 7.00% | $5,322.42 | $6,202.39 | $7,190.63 |
| 7.25% | $5,457.41 | $6,323.01 | $7,302.90 |
| 7.50% | $5,593.72 | $6,444.75 | $7,416.10 |
At 6.5%, interest alone on $800,000 runs about $4,333.33 per month — roughly $142.47 every day. That's the number amortization slowly kills: each payment shrinks the balance, so each month a little less goes to interest and a little more to principal. See the month-by-month schedule, or try our daily interest calculator for per-diem closing math.
Principal and interest is the floor, not the payment. A realistic budget adds property taxes, homeowners insurance, HOA dues, and — under 20% down — mortgage insurance, which our full calculator prices the way a lender does: FHA and USDA from the official tables, VA's funding fee, and conventional PMI by credit score.
A common guideline caps total housing costs near 28–36% of gross income, but real qualifying depends on your full debt picture, credit and loan program. Build the complete payment in the calculator, then ask a licensed professional — Phil answers questions free.
With 20% down, a $800,000 loan buys about $1,000,000 of house; with 5% down, about $842,105. Enter your own down payment in the payment calculator and the price, loan and LTV solve automatically.