I'm now finishing an estate income tax return which owes $250K federal taxes (41% rate). Widower of the deceased insists on sending a check. If it gets lost on its way to the 18th of April, I dread to think what the penalty will be. I will tell him to send it certified mail. To Virginia -- I don't even know what address to send it to. Anyone from Virginia can tell me please? Address is not in the software that I could find. So I was thinking of sending the money with the extension voucher instead.