Thanks for your advice. The client didn't know any thing about S Corp or Corp with the former CPA. He knew that after I explained to him about it.  The former CPA hasn't done any extension filed before March15th due date. I faxed 2553 with relief request to IRS and wait for approval. I don't know if the late election to be S Corp is valid or not. Can you explain to me what requirement for late election be S corp is valid? I really appreciate it.