RPG Consultants files a form 5558 for all clients (for whom we are responsible to prepare their 5500) in the second quarter. This form grants an automatic 2.5 month extension of time to file the annual Form 5500. For example, a calendar year plan will now have their 5500 due on 10/15 instead of 7/31. We do this because, even though many of our clients receive their completed 5500s before 7/31, we do not have a guarantee that the client will submit it before the first deadline. And, since the 5500 has a box that must be checked indicating a 5558 was filed, it is best to file one for all clients on a "protect" basis.
If you receive a confirmation that the extension was granted, simply file it with your retirement plan documents. We do not need a copy.