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HMRC internal manual

VAT Traders’ Records Manual

Computer invoicing: Value Added Network Services (VANS)

These networks offer an extensive range of services, but they basically act as electronic post offices for the transfer of data between trading partners. The sender transmits his data into his VANS post box and the VANS service checks the destination address of the data, and then transfers it into a VANS mailbox for collection by the recipient. This type of service tends to be used by larger traders but is not exclusive to them.