What Is Amortization?
Amortization is the process of paying off a loan through regular installments of principal and interest. Learn how amortization schedules work for mortgages and loans.
Definition
Amortization is the process of paying off a loan over time through a series of regular, equal payments. Each payment covers both interest and a portion of the principal (the original loan amount). In the early years, most of your payment goes toward interest. Over time, the interest portion shrinks and the principal portion grows -- this shift is the key to understanding amortization.
An amortization schedule is a table that shows the breakdown of each payment into interest and principal for the life of the loan. For a 30-year mortgage, this schedule has 360 rows (one for each monthly payment). In the first month, you might pay $1,500 in interest and only $300 toward principal. By year 25, those proportions are reversed.
The concept applies to any installment loan: mortgages, car loans, student loans, and personal loans. It can also refer to spreading the cost of an intangible asset (like a patent or software) over its useful life in accounting.
Real-World Example
You take out a $300,000 mortgage at 6% interest for 30 years. Your monthly payment is about $1,799. In month one, $1,500 goes to interest and only $299 goes to principal. By month 180 (year 15), the split is roughly $1,050 in interest and $749 in principal. By month 348 (year 29), nearly the entire payment ($1,768) goes to principal. Over the full 30 years, you pay a total of about $647,000 -- meaning $347,000 goes to interest alone.
Why It Matters
Understanding amortization reveals the true cost of long-term loans. Most homeowners are shocked to learn that they pay more in interest than the original loan amount on a 30-year mortgage. This knowledge motivates strategies like making extra principal payments (which can shave years off a mortgage and save tens of thousands in interest), choosing 15-year over 30-year mortgages, or refinancing when rates drop.
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Frequently Asked Questions
Why do I pay so much interest in the beginning of a loan?
Interest is calculated as a percentage of the remaining balance. At the start, your balance is highest, so the interest charge is highest. As you pay down principal, the balance shrinks and less interest accrues each month.
How can I pay off my mortgage faster?
Make extra principal payments, switch to biweekly payments (26 half-payments = 13 full payments per year instead of 12), or refinance to a shorter term. Even small extra payments can save thousands in interest.
What is the difference between amortization and depreciation?
Amortization applies to intangible assets or loans. Depreciation applies to physical assets (buildings, equipment, vehicles). Both spread costs over time, but they apply to different types of assets.
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