There are many differences between amortization and depreciation. Below is a definition of each to assist you in determining whether amortization or depreciation applies to the asset in question.
Per IRS Instructions for Form 4562 Depreciation and Amortization (Including Information on Listed Property), on page 1:
Depreciation is the annual deduction that allows you to recover the cost or other basis of your business or investment property over a certain number of years. Depreciation starts when you first use the property in your business or for the production of income. It ends when you either take the property out of service, deduct all your depreciable cost or basis, or no longer use the property in your business or for the production of income.
On page 2:
Amortization is similar to the straight line method of depreciation in that an annual deduction is allowed to recover certain costs over a fixed time period. You can amortize such items as the costs of starting a business, goodwill, and certain other intangibles. See the instructions for Part VI.
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