Once registered, a registrable person is required to submit a landfill tax return (form LT 100). This will normally be for an accounting period of three months and it is due by the last day of the month following the end of the accounting period.
When tax becomes due and payable
Tax falls due when a taxable disposal is made. However, if within 14 days of the disposal, the landfill operator issues a landfill tax invoice, the disposal is treated as having been made on the invoice date.
The 14-day period may be extended by negotiation with HMRC (e.g. to allow for monthly invoicing).