re: Underpayment penalty on taxes......Paging Poodle...please see last post

Short term disability benefits are NOT taxable income. Unless the benefits exceeded more than the 66.7% of gross pay maximum. If your accountant doesn't know this, then I'd fire his arse, and see if you can get a new return before the 15th. If you can't, file the return and pay something on time, then file an amended return asap with a new accountant.