French amortization for mortgages, explained
Understand level mortgage payments and the changing split between interest and principal.
The French amortization method keeps the scheduled principal-and-interest payment level when the rate and terms remain fixed. Interest is calculated from the outstanding balance, so early payments contain more interest and later payments contain more principal.
For $2,000,000 at 9%, first-month interest is $15,000. From the $17,994.52 payment, $2,994.52 reduces principal. In month two, interest falls to $14,977.54 and principal rises to $3,016.98.
This does not mean all interest is charged upfront. The balance is simply largest at the start. Other systems may use constant principal and declining payments.
The mortgage calculator uses this level-payment assumption. Always compare it with the institution’s formal schedule because not every mortgage follows identical rules.