diff --git a/src/pretix/base/models/invoices.py b/src/pretix/base/models/invoices.py
index c5cd067dd0..c49fd79268 100644
--- a/src/pretix/base/models/invoices.py
+++ b/src/pretix/base/models/invoices.py
@@ -120,13 +120,19 @@ class Invoice(models.Model):
 
     @property
     def full_invoice_from(self):
+        taxidrow = ""
+        if self.invoice_from_tax_id:
+            if str(self.invoice_from_country) == "AU":
+                taxidrow = "ABN: %s" % self.invoice_from_tax_id
+            else:
+                taxidrow = pgettext("invoice", "Tax ID: %s") % self.invoice_from_tax_id
         parts = [
             self.invoice_from_name,
             self.invoice_from,
             (self.invoice_from_zipcode or "") + " " + (self.invoice_from_city or ""),
             self.invoice_from_country.name if self.invoice_from_country else "",
             pgettext("invoice", "VAT-ID: %s") % self.invoice_from_vat_id if self.invoice_from_vat_id else "",
-            pgettext("invoice", "Tax ID: %s") % self.invoice_from_tax_id if self.invoice_from_tax_id else "",
+            taxidrow,
         ]
         return '\n'.join([p.strip() for p in parts if p and p.strip()])
 
diff --git a/src/pretix/base/settings.py b/src/pretix/base/settings.py
index cf4efa8934..f0f6059c3d 100644
--- a/src/pretix/base/settings.py
+++ b/src/pretix/base/settings.py
@@ -527,6 +527,7 @@ DEFAULTS = {
         'serializer_class': serializers.CharField,
         'form_kwargs': dict(
             label=_("Domestic tax ID"),
+            help_text=_("e.g. tax number in Germany, ABN in Australia, …")
         )
     },
     'invoice_address_from_vat_id': {