A system generated code is allocated to each entity created in Varibill. This code can be overwritten with a unique code. This code will be used to uniquely identify each individual entity created and is not used during billing validation, billing processing or updating your accounting system.
This code will be used to uniquely identify each entity when posting create, read, update, delete requests through the Varibill API's. This code will also be used with the Varibill Excel Add-In.
For more information, refer to docs.varibill.com.