> ## Documentation Index
> Fetch the complete documentation index at: https://help.exy.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# How VAT and billing address are applied

> Why tax can change and where to update billing details.

VAT is calculated when a new invoice is created, based on your current billing address data.

If you want correct invoice tax details:

1. Open Billing -> Billing Address.
2. Save your country, postal data, and optional VAT ID.
3. Create the order, renewal, top-up, or IP-change invoice after the address is updated.

Already created invoices keep their original tax calculation.


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