Accelerated Depreciation

Any method of depreciation used for accounting or income tax purposes that allows greater deductions in the earlier years of the life of an asset.

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The straight-line depreciation method spreads the cost evenly over the life of an asset. On the other hand, a method of accelerated depreciation like the double declining balance (DDB) allows you to deduct far more in the first years after purchase.

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Depreciation methods, chosen for income tax or accounting purposes, that offer greater deductions in early years.

The straight-line method, rather than accelerated depreciation, generally applies to buildings bought after 1986. See macrs.
Example: One method of accelerated depreciation is the double declining balance method (DDB). If straight-line deductions equal 5% of depreciable basis, DDB allows a deduction of 10% (200% of 5%), but applied to the undepreciated basis. Thus the deductions decline each year.

Method recognizing higher amounts of depreciation in the earlier years and lower amounts in the later years of a fixed asset's life. Some machines, for example, are more efficient early on and generate greater service potential; matching dictates higher depreciation expense in those years. Over time, depreciation expense moves in a downward direction and maintenance costs tend to become higher; thus the effect of accelerated depreciation is fairly even charges to income. Greatest tax benefits from depreciation are enjoyed in the earlier years. See also Accelerated Cost Recovery System; Double Declining Balance; Sum-Of-The-Years'-Digits (SYD) Method.