HMRC provide the following guidance :
- Transit movements involving goods which are being exported from GB or XI must be associated with an Export Declaration MRN made to CDS - Customs Declaration Service.
- This Export Declaration MRN should be referenced in the Transit Declaration at the most appropriate declaration level: Consignment, House Consignment, or Consignment Item, in either the ‘Previous Document’ or ‘Supporting Document’ data groups.
- If using the Previous Document data group, the Type data element derived from CL214 (Previous Document Type) should be NMRN - Declaration/Notification MRN, or an established alternative which does not confuse the nature of the previous document in countries of destination.
- If using the Supporting Document data group, the Type data element derived from CL213 (Supporting Document Type) should be NZZZ - Document equivalent to ‘ZZZ’ defined in Commission Delegated Regulation (EU) 2016/341 (Appendix D2: Additional codes for the computerised transit system).
- Use of these codes is part of a workaround to bypass the actual export declaration MRN reference N830 (Goods declaration for exportation) which, due to overlap with specific AES (Automated Export System) functionality, cannot currently be used for goods exported from the UK moving via transit without restricting the Office of Destination able to be declared to only those which double as an EU Office of Exit (a customs office at the border of the EU which handles EU Export Declarations).
- If your intended Office of Destination for the transit procedure, is, an office of exit - Previous Document reference N830 may be used without issue at the House Consignment level of the declaration.
- When AES functionality is established in XI - N830 may be used for transit movements containing EU export goods departing from an XI (Northern Ireland) Office of Departure and will be necessary to ensure proper interaction between NCTS and AES on outbound EU export goods.