The Internal Revenue Service said that interest rates would remain the same for the calendar quarter beginning Jan. 1, 2010, as they were in the prior quarter.
The rates will be 4 percent for overpayments, or 3 percent in the case of a corporation; 4 percent for underpayments; 6 percent for large corporate underpayments; and 1.5 percent for the portion of a corporate overpayment exceeding $10,000.
Under the Tax 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 of a percentage point.
