Full Amortization Schedule Calculator

An amortization schedule is a complete table of every mortgage payment over the life of the loan, showing how each payment splits between principal reduction and interest. In early years, the vast majority of each payment is interest — on a 30-year loan at 7.25%, month-1 interest is about 87% of the total payment. This ratio gradually shifts until the final payment is nearly all principal.

Because interest is calculated on the remaining balance. In month 1, that balance is the full loan amount, so interest is high. As principal is paid down, the balance decreases and interest charges drop — very slowly at first, then accelerating. This is the nature of amortization: payments are level, but the composition shifts. It's not a trick of lenders — it's pure math.

On a 30-year $350,000 loan at 7.25%, after 5 years (60 payments) you'll have paid approximately $16,000 in principal and $113,000 in interest. The balance will be roughly $334,000. Equity from amortization alone is modest in early years — most early-stage equity building comes from property appreciation, not loan paydown.

A 20-year loan has higher monthly payments but builds equity much faster and costs significantly less in total interest. On a $350,000 loan at 7.25%: 30-year payment is ~$2,388/month with ~$510,000 in total interest; 20-year payment is ~$2,765/month with ~$313,000 in total interest. You pay $377/month more but save $197,000 in interest and own the property free-and-clear 10 years sooner. Most DSCR lenders offer both 30-year and 20-year options.

Yes, but prepayment penalties apply during the PPP window (typically 3–5 years). After the penalty period expires, you can make additional principal payments freely. Each extra dollar of principal payment reduces your balance, future interest charges, and shortens the payoff timeline. If you're past the PPP window, even modest extra payments can shave years off a 30-year mortgage.

During the interest-only period, there is no amortization — the balance stays flat and 100% of each payment is interest. After the I/O period ends, the loan converts to a fully amortizing schedule for the remaining term. On a 30-year loan with a 10-year I/O period, years 11–30 amortize the full original balance over 20 years (not 30), resulting in higher payments. See the Interest-Only vs Amortizing calculator for a direct comparison.

Some DSCR lenders offer 40-year amortization (vs. the standard 30-year). The monthly payment is lower because the principal is spread over more months, but the total interest paid over the life of the loan is significantly higher. On a $350,000 loan at 7.25%: 30-year payment is $2,388 and total interest is $510K; 40-year payment is $2,207 and total interest is $710K. The payment drop is ~$181/month but total interest is $200K higher.

The crossover point — where each monthly payment's principal component exceeds the interest component — occurs roughly in the middle third of the loan term. On a 30-year loan at 7.25%, this crossover happens around month 257 (year 21). Before that, you're paying more interest than principal each month. This is why early payoff or sale in the first 10–15 years leaves most of the balance outstanding.