GST refunds: defined triggers include excess payments, export credits, assessment adjustments and input credit accumulation. Refunds under GST and legacy taxes arise where the administration owes amounts to taxpayers, notably for excess payments; export-related rebates or recovery of accumulated input credit; finalization of provisional assessments; appellate pre-deposit repayments; investigation-related adjustments; diplomatic and international organization purchases; and input credit accumulation caused by exempt or nil-rated outputs, inverted duty structures, supplier credit notes, or tourist refund schemes.