43.1 Standard Mileage Rate
If you start to use your car for business in 2012, you have a choice of either deducting the actual operating costs of your car during business trips or deducting a flat IRS allowance. The allowance is 55.5¢ per mile. The mileage allowance also applies to business trips in a van or pickup or panel truck as if it were a car.
If you placed a car, van, pick-up, or panel truck in service before 2012 and have always used the IRS mileage allowance, you may apply the cents-per-mile rate to your 2012 business mileage or deduct your actual operating costs plus straight-line depreciation over the remaining estimated useful life of the vehicle (assuming the vehicle is not considered fully depreciated).
The rate may not be used to deduct the costs of a vehicle used for nonbusiness income-producing activities such as looking after investment property.
Allowance must be elected for the first year.
The choice of the allowance must be made in the first year you place the vehicle in service for business travel. If you do not use the allowance in the year you first use the vehicle for business, you may not use the allowance for that vehicle in any other year. Thus, if you bought a car for business in 2011 and on your 2011 return you deducted actual operating costs plus depreciation, you may not use the mileage allowance on your 2012 return or in any later year.