Home and Monthly Cost Inputs
Compare Rate Options
Without Promotion
Standard Rate
With Promotion
Promotional Rate
Payment With Promotion
Select a promotional option to compare payments.Payment Without Promotion
Estimated monthly payment using the selected standard rate.Estimated Monthly Savings
Select a standard rate and a promotional option to compare payments.3-2-1 Buydown Payment Schedule
This promotional option temporarily reduces the interest rate used for the estimated payment in years 1, 2, and 3, then returns to the note rate for years 4 through 30.
How This Calculation Is Made
The calculator starts with the estimated loan amount, which is the home price minus the down payment. It then calculates principal and interest using a standard fixed rate mortgage amortization formula based on the selected interest rate and loan term.
In the formula, L is the loan amount, r is the monthly interest rate, and n is the total number of monthly payments. The estimated monthly payment shown on the page adds monthly property taxes, homeowners insurance, and PMI or mortgage insurance to the principal and interest estimate.
APR is displayed for comparison and disclosure context, but the monthly principal and interest calculation uses the interest rate selected in the calculator. For the 3-2-1 buydown, the displayed year by year payments use the temporary buydown rates for years 1, 2, and 3, then the note rate for years 4 through 30.