SF Depreciation

The SF depreciation method is very similar to the SL depreciation method, except that it uses the full month averaging convention.

The first step in calculating depreciation for depreciation method SF is to calculate the adjusted basis. The formula for calculating the adjusted basis is:

Original Cost - Salvage Value

=

Adjusted Basis

 

The formula for calculating straight-line depreciation is:

Adjusted Basis
Estimated Life

=

Annual Depreciation

 

Here is an example:

Original Cost:

$14,000

Salvage Value:

$2,000

Placed-in-service Date:

04/16/2021

Estimated Life:

5 Years

 

First, calculate the adjusted basis:

$14,000 - $2,000

=

$12,000

Next, calculate the annual depreciation:

$12,000
5

=

$2,400

Year 1:

$2,400

X

9 *
12

=

$1,800

* The SF depreciation method uses the full month averaging convention. The asset is treated as though it were placed in service on April 1. It receives a full month of depreciation in April and 9 months of depreciation in the first year.

Years 2 through 5:

In years 2 through 5, the asset receives the yearly depreciation of $2,400 (as calculated above).

Year 6:

$2,400

X

3
12

=

$600

In the final year, the asset receives 3 months of depreciation.