If you filed for an extension to file your taxes, the due date for individuals is Oct. 15.
However, if a corporation, S-corporation or partnership filed an extension, the due date to file this return is Sept. 17. Preparing financial statements for these types of businesses will help in completing the return, as the return is very similar to these statements.
An extension must have been filed for corporations and S-corporations by March 15. Failing to file an extension will result in a penalty that is assessed at $195 per month or part month, up to 12 months, multiplied by the number of shareholders. This penalty is steep because it extends to the number of shareholders involved.