NEW POST OFFICE DATE LAWS: (If paying last minute) You must go in to the post office to have it stamped with the date processed, or it will be returned for the proper amount plus the penalty due at the time received, not the date you dropped it in the mailbox. This must be a US Postal Service postmark.
**All money must be exact, cannot be rounded up, or down. That includes when you are paying penalties.  Please refer to your bill. **