How the Principal Calculator Works

Every payment on a fixed-rate mortgage is the same size, but the split between interest and principal changes every month. Interest for a given month is simply your remaining balance × the monthly rate; whatever is left of the fixed payment after that goes to principal. Early in the loan, most of the payment is interest because the balance is high; late in the loan, most of it is principal because the balance is low.

This calculator walks the full amortization schedule so you can see your principal balance, and the interest/principal split of each payment, at any point over the life of the loan.

California rules & 2026 figures that apply

• Under the federal Homeowners Protection Act, your servicer must automatically cancel private mortgage insurance (PMI) once your loan balance is scheduled to reach 78% of the home's original value (as long as you're current), and you can request cancellation in writing once you reach 80% (NCUA, Homeowners Protection Act summary).
• The federal mortgage interest deduction caps acquisition debt at $750,000. California does not conform to that federal cap - a CA state return can still deduct interest on up to $1 million of acquisition debt on a qualified principal residence, so some CA homeowners can deduct more on their state return than on their federal return. This is general information, not tax advice - confirm your situation with a CPA (California FTB, 2025 Schedule CA (540) instructions).

Estimates only, not a commitment to lend. Figures above reflect publicly reported 2026 program limits and CA tax rules as of this writing and can change - confirm current numbers and your specific eligibility with one of our loan officers before making a decision. The Home and Commercial Loan Company, Inc. is an Equal Housing Opportunity lender, NMLS #1665729.