Last month, the IRS released an updated version of Form 5558, "Application for Extension of Time to File Certain Employee Plan Returns." In prior versions, the Form 5558 was used to provide either a one-time extension of the due date for the filing of a Form 5500 Series Return for a plan (meaning a Form 5500, a Form 5500-SF or a Form 5500-EZ Return), or to request an extension of time for filing of a Form 5330 to report excise taxes associated with an employee benefit plan.
As was the case in prior versions, no signature is required if the Form 5558 is used to extend the due date for filing of a Form 5500 Series Return. For a Form 5330 extension request, however, a signature is still required. You must also still provide an explanation on the Form 5558 as to why you need an extension of time.
It's worth mentioning that the Form 5558 does not extend the due date for the payment of any excise taxes due; only the reporting of the excise taxes. Once a Form 5558 is submitted, the IRS will grant only a reasonable extension of time (not to exceed 6 months) for filing of the Form 5330, and only if you are unable to file the Form 5330 timely due to circumstances beyond your control.
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