How is tax charged on my subscription?

Plan prices are shown before tax. If you installed nouz from the Shopify App Store, your plan is part of your Shopify bill. Shopify adds whatever tax it must charge in your region. A payment that fails is handled the same way, as part of that bill.

If nouz bills you directly in euro, VAT is added at checkout. VAT is the sales tax of the European Union. It depends on your billing country. A business in another EU country with a valid VAT ID pays no VAT on the invoice. This is called reverse charge. Outside the EU, there is no EU VAT.

You can update your VAT ID later in Settings, under Billing. Every invoice is made for you and kept there. The full amount, with tax, is always shown before anything is charged.