Switching to IOSS or Union OSS becomes beneficial when your business ships goods to multiple member states. In that case having a single registration to manage your VAT can add efficiency to your business process. Your business only deals the with tax authority of the member state in which you have registered for the OSS. Via the OSS your VAT payments will be distributed to the relevant member states.
Besides a single registration, other uniform VAT rules apply such as a unified standard for the VAT administration, VAT return, submission deadlines and retention period of relevant documents.
Consumers may also experience great benefits of the IOSS scheme. Upon sale the consumer pays the VAT and will not be surprised by unexpected fees. Delivery including the required customs clearance will run smoothly.