Today the IRS issued Revenue Ruling 2015-5, which provides the rates for interest on tax overpayments and underpayments for the calendar quarter beginning April 1, 2015.  The interest rates will be three percent for overpayments (two percent in the case of a corporation), three percent for underpayments, one-half percent for the portion of a corporate overpayment exceeding $10,000, and five percent for large corporate underpayments.