Partial Business Use of Vehicles – What is Deductible?

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Since many of our clients use a vehicle for both business and personal use, we thought a refresher on this topic would be useful as we approach year-end. It is quite acceptable to use a vehicle for both business and personal use but important to understand the deductibility of expenses associated with the vehicle.

Business use is determined by the number of miles traveled between two business locations. The business use percentage is simply the ratio of total business miles for the year to total miles for the year for the vehicle. As a reminder, commuting miles to and from your normal place of business are not considered to be business miles.

When you use a vehicle for business purposes, the business portion of depreciation and ordinary and necessary vehicle operating expenses are deductible. The tax regulations provide two methods for calculating the business portion of vehicle expenses which can be used by self-employed taxpayers and employees:

(1) the deduction may be computed using the standard mileage rate for the number of business miles driven during the year, or

(2) the business portion of actual vehicle expenses, including depreciation and the Section 179 deduction, may be deducted.

Standard Mileage Rate Method:

The standard mileage rate varies from year to year and is computed by the IRS to represent the cost of fuel, oil, insurance, repairs and maintenance and depreciation or lease payments for the vehicle. The standard mileage rate method is available regardless of the cost of the vehicle. For 2014, the standard mileage rate is $.56 per mile.

In addition to the standard mileage rate, the costs of business-related parking and tolls are 100 percent deductible. The standard mileage rate can only be used if this method was used to compute the business auto deduction for the first year the vehicle was placed in service and each subsequent year. If the standard mileage rate is used to calculate the vehicle expense deduction for a vehicle, straight-line depreciation must be used if there is a subsequent switch to the actual expense method.

Actual Expenses Method:

To use the actual expense method, first determine the entire cost of operating the vehicle for the year, including vehicle depreciation and Section 179 expense, if any.

Taxpayers who use a vehicle more than 50% of the time for a qualified business use can deduct Section 179 expense and/or MACRS accelerated and bonus depreciation, as well as other ordinary and necessary expenses. If the vehicle is used less than 50% for qualified business use, straight line depreciation over a 5-year life must be used to compute depreciation on the vehicle and the Section 179 deduction is not available for the vehicle.

The above rules are subject to the limitations on luxury vehicles. Certain trucks, vans and sports utility vehicles with a gross loaded vehicle weight rating exceeding 6,000 pounds  are not subject to the luxury auto depreciation limits.*** However, vehicles with a weight rating of 6,000 pounds or less are considered passenger autos and are subject to the luxury vehicle limitations.

To satisfy the more than 50% qualified business use test, only use in a trade or business can be considered. Investment use and other use in other activities conducted for the production of income are not included in the qualified business use test, although total business and investment use can be used for determining the deductible portion of vehicle expenses.

If qualified business use falls below 50% in subsequent years, then depreciation and Section 179 deductions in excess of the straight-line method and deducted in previous years must be recaptured in the year that qualified business use falls below 50%.

Of course, we recommend that you keep excellent vehicle expense documentation and contemporaneous usage records. We have included a vehicle mileage log (see side bar) that we recommend you keep to corroborate auto usage documentation from repair and maintenance records.

If you have questions regarding the information in this article or if you’re interested in special tax deductions related to the purchase of a truck, van or sports utility vehicle in 2014, please give a member of the SKR staff a call to learn more.

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