Unfortunately, the IRS does not confirm acceptance of Form 5558 filings. But we rarely see issues with extensions not being accepted. In addition, we file our extensions under a certified letter that shows evidence of the filing. So we rarely see problems with extension filings. Clients need to make sure they communicate to us the need for an extension filing, even though we will generally file one if we don't have enough information to file form 5500. As long as you have communicated with us the desire to file an extension, we take responsibility for getting the extension filed and dealing with the IRS in case they claim it was not received.