I have a client that had a 401(k) Simple plan for 3 years, then amended it to a 401(k) safe harbor plan for the next 2 years. Now, the plan is no longer safe harbor and is subject to the ADP test. Regulations say that a safe harbor plan uses the current year testing method. The client wants to now use the prior year testing method. A plan cannot be amended to use the prior year method until it has used the current year method for 5 years. Could the 3 years the plan was a Simple 401(k) (and not subject to testing) count towards the 5 years?

I have not seen anything in writing on this (nor have I researched) however, I think that you would only count the years that testing would apply. Since testing didn't apply when it was a SIMPLE (k), I don't think you could count those years when determining the 5 year testing cycle.

What was put in the "GUST Remedial Amendment Period Elections" for 401(k) testing methods?