I am ready to file 941 for the 4th quarter of 2016, and realized I made overpayment on the October and November, can I ask for a refund? and Do I need to file 941X? I haven't file 941 for Q4 2016 yet.
That's actually a good thing. I ALWAYS overpay my quarterly taxes. That way, I am one hundred percent guaranteed that I will get a refund when I file my tax return. So nothing to worry about. Your overpayment will be refunded to you when you file your 2016 tax return.