The registered general insurer must lodge a return with the Agency showing all premiums collected in the preceding month, and pay the appropriate duty, on or before the 21st day of each month.
If an insured party is liable, that party must lodge a return with containing all the particulars, and pay the appropriate duty, within 21 days after the end of the month in which the relevant premium was paid.
Please note that a return must be lodged even if you do not have to pay any duty that month.