The IRS has announced the interest rates for tax overpayments and underpayments for the calendar quarter beginning April 1, 2009.
For noncorporate taxpayers, the rate for both underpayments and overpayments will be 4% (down from 5%).
For corporations, the overpayment rate will be 3% (down from 4%). Corporations will receive 1.5% (down from 2.5%) for overpayments exceeding $10,000. The underpayment rate for corporations will be 4% (down from 5%), but will be 6% (down from 7%) for large corporate underpayments.
Rev. Rul. 2009-7