The tax return is due on or before the 20th day of the month following the close of the calendar month or quarter reporting period. Interest and penalties will be assessed on delinquent returns and/or payments. NOTE – In addition to the delinquent penalties reported above, a taxpayer may also incur a negligence penalty under LA R.S. 47:1604.1 if circumstances indicate willful negligence or intentional disregard of rules and regulations. Also, an examination fee may be imposed in the event the Department is required to issue a billing notice necessitated by the filing or lack of filing of this return.