A Supplementary Declaration (SD) is a post-shipment declaration that provides information used to control and work out duty for export and import consignments, as well as to gather statistical data on international trade. This guide explains the three different types of SD, and when traders must complete each one.
Tips are given on the most efficient way to submit declarations. This guide also explains how the information traders give is used to work out the duty they must pay. You will also find information on the Customs Handling of Import and Export Freight (CHIEF) system, enforcement of HM Revenue & Customs procedures and sources of more advice and support.
This guide contains intermediate information. For additional intermediate and detailed information, see our section on customs declarations.