How to Calculate Amount of Principal Left on a Mortgage

The principal amount of a mortgage is the original or beginning amount of your mortgage loan. You can calculate the amount of principal left on a mortgage. Keep in mind that the method used below takes into consideration that set payments have been paid on time, preventing additional interest from accruing.

Instructions

Difficulty: Moderate

1. Find out the original mortgage amount. Find out your interest rate. Take your original principal loan amount. Multiply that times your interest rate in order to calculate the amount of principal that's left on a mortgage.
2. Divide the last amount figured in Step 1 by 360. (Interest is figured on a 360-day year.) This gives your daily interest. Take that daily interest and multiply that by 365 days in the year. Divide that figure by 12 (total months in a year). This is the amount of interest paid on a monthly basis.
3. Take the total principal and interest payment (no PMI or escrows included) and subtract the monthly interest amount. This gives you your principal based on a 12-month calendar.
4. Determine the total amount of mortgage payments made to date in order to calculate the amount of principal left on your mortgage. For example, if you have been in your home for two years, making regular payments, multiply the monthly payment by 24. Multiply that amount times the monthly principal just calculated in Step 3.
5. Subtract that amount from the original loan amount and this gives you the amount of principal left. (This method gives you a close estimate.)

Tips & Warnings

• Keep in mind that in the beginning of a mortgage, you pay mostly interest. Then, over time, it flip-flops back and forth between principal and interest over the life of the mortgage.
• See the Resource below for a website calculator that uses an amortization schedule that can figure principal balance to the penny.