Discover details about how the IRS treats excess contributions to simplified employee pension plans (SEPs). 

An employee may avoid the 6% excise tax on excess SEP contributions, and the 10% early distribution tax on the early withdrawal of the excess contributions, by withdrawing excess contributions from his SEP-IRA on or before the due date (including extensions) for filing the employee's income tax return for the tax year for which the contributions were made (Code Sec. 408(d)(4)).