The short answer: at a 6.5% rate, a $850,000 30-year fixed mortgage costs $5,372.58 a month in principal and interest; at 7%, $5,655.07. On a 15-year term at 6.5% the payment is $7,404.41. 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% | $4,562.98 | $5,609.62 | $6,721.75 |
| 5.25% | $4,693.73 | $5,727.68 | $6,832.96 |
| 5.50% | $4,826.21 | $5,847.04 | $6,945.21 |
| 5.75% | $4,960.37 | $5,967.71 | $7,058.49 |
| 6.00% | $5,096.18 | $6,089.66 | $7,172.78 |
| 6.25% | $5,233.60 | $6,212.89 | $7,288.09 |
| 6.50% | $5,372.58 | $6,337.37 | $7,404.41 |
| 6.75% | $5,513.08 | $6,463.09 | $7,521.73 |
| 7.00% | $5,655.07 | $6,590.04 | $7,640.04 |
| 7.25% | $5,798.50 | $6,718.20 | $7,759.33 |
| 7.50% | $5,943.32 | $6,847.54 | $7,879.61 |
At 6.5%, interest alone on $850,000 runs about $4,604.17 per month — roughly $151.37 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 $850,000 loan buys about $1,062,500 of house; with 5% down, about $894,737. Enter your own down payment in the payment calculator and the price, loan and LTV solve automatically.