WASHINGTON ― The Internal Revenue Service today announced that interest rates will remain the same for the calendar quarter beginning Jan. 1, 2014.  The rates will be:

• three (3) percent for overpayments [two (2) percent in the case of a corporation];
• three (3) percent for underpayments;
• five (5) percent for large corporate underpayments; and
• one-half (0.5) percent for the portion of a corporate overpayment exceeding $10,000.

Under the Internal Revenue Code, the rate of interest is determined on a quarterly basis.  For taxpayers other than corporations, the overpayment and underpayment rate is the federal short-term rate plus 3 percentage points.

Generally, in the case of a corporation, the underpayment rate is the federal short-term rate plus 3 percentage points and the overpayment rate is the federal short-term rate plus 2 percentage points. The rate for large corporate underpayments is the federal short-term rate plus 5 percentage points. The rate on the portion of a corporate overpayment of tax exceeding $10,000 for a taxable period is the federal short-term rate plus one-half (0.5) of a percentage point.

The interest rates announced today are computed from the federal short-term rate determined during Oct. 2013 to take effect Nov. 1, 2013, based on daily compounding.

Revenue Ruling 2013-25 announcing the quarterly rates will be published  in Internal Revenue Bulletin 2013-52, dated Dec. 23, 2013.

WASHINGTON — The Internal Revenue Service today issued the 2014 optional standard mileage rates used to calculate the deductible costs of operating an automobile for business, charitable, medical or moving purposes.

Beginning on Jan. 1, 2014, the standard mileage rates for the use of a car (also vans, pickups or panel trucks) will be:

• 56 cents per mile for business miles driven
• 23.5 cents per mile driven for medical or moving purposes
• 14 cents per mile driven in service of charitable organizations

The business, medical, and moving expense rates decrease one-half cent from the 2013 rates.  The charitable rate is based on statute.

The standard mileage rate for business is based on an annual study of the fixed and variable costs of operating an automobile. The rate for medical and moving purposes is based on the variable costs.

Taxpayers always have the option of calculating the actual costs of using their vehicle rather than using the standard mileage rates.

A taxpayer may not use the business standard mileage rate for a vehicle after using any depreciation method under the Modified Accelerated Cost Recovery System (MACRS) or after claiming a Section 179 deduction for that vehicle.  In addition, the business standard mileage rate cannot be used for more than four vehicles used simultaneously.

These and other requirements for a taxpayer to use a standard mileage rate to calculate the amount of a deductible business, moving, medical, or charitable expense are in Rev. Proc. 2010-51.  Notice 2013-80 contains the standard mileage rates, the amount a taxpayer must use in calculating reductions to basis for depreciation taken under the business standard mileage rate, and the maximum standard automobile cost that a taxpayer may use in computing the allowance under a fixed and variable rate plan.