The nature of the transaction
1. Transactions involving actual or intended transfer of ownership from residents to non-residents against financial or other compensation (except the transactions listed under 2, 70 and 80)
11. Outright purchase/sale
12. Supply for sale on approval or after trial, for consignment or with the intermediation of a commission agent (including stock movements from one Community Country to another)
13. Barter trade (compensation in kind)
14. Financial leasing (hire-purchase) 
2. Return and replacement of goods free of charge after registration of the original transaction
21. Return of goods
22. Replacement for returned goods
23. Replacement (e.g. under warranty) for goods not being returned
30. Transactions involving transfer of ownership without financial or in kind compensation (e.g. aid shipments)
4. Operations with a view to processing under contract (no transfer of ownership to the processor) 
41. Goods expected to return to the initial Member State of dispatch
42. Goods not expected to return to the initial Member State of dispatch
5. Operations following processing under contract (no transfer of ownership to the processor)
51. Goods returning to the initial Member State of dispatch
52. Goods not returning to the initial Member State of dispatch
60. Goods imported or exported for repair and returned after repair 
70. Operations under joint defence projects or other joint intergovernmental production programs
80. Transactions involving the supply of building materials and technical equipment under a general construction or civil engineering contract for which no separate invoicing of the goods is required and an invoice for the total contract is issued.
9. Other transactions which cannot be classified under other codes
91. Hire, loan, and operational leasing longer than 24 months
 Financial leasing covers operations where the lease instalments are calculated in such a way as to cover all or virtually all of the value of the goods. The risks and rewards of ownership are transferred to the lessee. At the end of the contract the lessee becomes the legal owner of the goods.
 Processing covers operations (transformation, construction, assembling, enhancement, renovation…) with the objective of producing a new or really improved item. This does not necessarily involve a change in the product classification. Processing activities on a processor’s own account are not covered by this item and should be registered under item 1.
 Repair entails the restoration of goods to their original function; this may involve some rebuilding or enhancements.