Assign Tax Groups to Items and Parties
Once your tax groups exist, assign them wherever tax needs to calculate — on products, customers, vendors, and document lines in Sales, Purchase, Inventory, POS, and Real Estate.
Resolution order
When a document line doesn't set a tax group explicitly, Biznsbook resolves one in this order:
Item's tax group → Party's tax group → Company default group
This same resolution is shared across Sales and Purchase (and any other module using the shared tax service), so the logic never diverges between them.
Tax-exempt parties and items
Mark a party or item tax exempt when it should skip tax entirely — for example an NGO customer or a zero-rated product. An exempt flag overrides the resolution order above.
:::info If tax shows as zero Check that the product, party, or line actually has a tax group assigned, that its components are active, and — if you're relying on the fallback — that a company default group exists. :::