EORI is used to connect the imported items and our VAT number.
If you want to do Amazon business in Europe countries, especially exporting or importing business. Then you will need the EORI number, or else the items will be detained in the customs, you can not get the VAT tax back.
Luckily, EORI is not difficult to register, you do not need to submit too many docs when registering. If the origin of the item is in Europe, then there is no need for the EORI number.
How to calculate VAT?
a) Production + shipping: 5€
b) Amazon fee: 5€
The total sales price at Amazon: 20€×1.2=24€
=4€ to the Government
Please note: VAT to suppliers/customs is deductible. All the sales prices on Amazon include the VAT, so remember to add it when you make the listings.