The tax deadline for S Corporation filing of a tax return is always by the 15th day of the third month that follows the end of the tax year. This is generally March (not April) 15. So it is already late.
If Form 1120S is not filed by the standard due date or the extended due date, the minimum penalty imposed by the IRS is $195 for each month or part of the month the return is late. The $195 is multiplied by the number of shareholders in the corporation.
