IRS interest rates are unchanged for the first quarter of 2014 (January 1, 2014, through March 31, 2014). These are the rates changed on underpayments and overpayments:
The 3% rate applies to underpayments of estimated taxes by individuals. All of these rates have held steady since October 1, 2011.
Source: Rev. Rul. 2013-25
An employer reimbursement or allowance arrangement that requires you to adequately substantiate business expenses to your employer, and to return any excess reimbursement.