yes that sounds like the simple answer, but the transfer was not from a regular checking account, and transfer involved a sale of stock first, and another 5 business day delay to post the money out because his bank wanted to hold the money for 5 business days to insure the funds cleared.  Taxpayer did not want to take a chance on being late and getting penalties.  the tax due on the federal was almost $175,000 which of course he did not keep that much in his checking account.