Allow country specific tax rules (#1714)

src/pretix/base/migrations/0156_cartposition_override_tax_rate.py

@@ -0,0 +1,18 @@
+# Generated by Django 3.0.6 on 2020-06-28 19:08
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0155_quota_release_after_exit'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='cartposition',
+            name='override_tax_rate',
+            field=models.DecimalField(decimal_places=2, max_digits=10, null=True),
+        ),
+    ]

src/pretix/base/models/items.py

@@ -448,24 +448,32 @@ class Item(LoggedModel):
             return self.event.settings.show_quota_left
         return self.show_quota_left
 
-    def tax(self, price=None, base_price_is='auto', currency=None, include_bundled=False):
+    def tax(self, price=None, base_price_is='auto', currency=None, invoice_address=None, override_tax_rate=None, include_bundled=False):
         price = price if price is not None else self.default_price
 
         if not self.tax_rule:
             t = TaxedPrice(gross=price, net=price, tax=Decimal('0.00'),
                            rate=Decimal('0.00'), name='')
         else:
-            t = self.tax_rule.tax(price, base_price_is=base_price_is,
-                                  currency=currency or self.event.currency)
+            t = self.tax_rule.tax(price, base_price_is=base_price_is, invoice_address=invoice_address,
+                                  override_tax_rate=override_tax_rate, currency=currency or self.event.currency)
 
         if include_bundled:
             for b in self.bundles.all():
                 if b.designated_price and b.bundled_item.tax_rule_id != self.tax_rule_id:
                     if b.bundled_variation:
-                        bprice = b.bundled_variation.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
+                        bprice = b.bundled_variation.tax(b.designated_price * b.count, base_price_is='gross',
+                                                         invoice_address=invoice_address,
+                                                         currency=currency)
                     else:
-                        bprice = b.bundled_item.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
-                    compare_price = self.tax_rule.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
+                        bprice = b.bundled_item.tax(b.designated_price * b.count,
+                                                    invoice_address=invoice_address,
+                                                    base_price_is='gross',
+                                                    currency=currency)
+                    compare_price = self.tax_rule.tax(b.designated_price * b.count,
+                                                      override_tax_rate=override_tax_rate,
+                                                      invoice_address=invoice_address,
+                                                      currency=currency)
                     t.net += bprice.net - compare_price.net
                     t.tax += bprice.tax - compare_price.tax
                     t.name = "MIXED!"
@@ -673,23 +681,31 @@ class ItemVariation(models.Model):
     def price(self):
         return self.default_price if self.default_price is not None else self.item.default_price
 
-    def tax(self, price=None, base_price_is='auto', currency=None, include_bundled=False):
+    def tax(self, price=None, base_price_is='auto', currency=None, include_bundled=False, override_tax_rate=None,
+            invoice_address=None):
         price = price if price is not None else self.price
 
         if not self.item.tax_rule:
             t = TaxedPrice(gross=price, net=price, tax=Decimal('0.00'),
                            rate=Decimal('0.00'), name='')
         else:
-            t = self.item.tax_rule.tax(price, base_price_is=base_price_is, currency=currency)
+            t = self.item.tax_rule.tax(price, base_price_is=base_price_is, currency=currency,
+                                       override_tax_rate=override_tax_rate,
+                                       invoice_address=invoice_address)
 
         if include_bundled:
             for b in self.item.bundles.all():
                 if b.designated_price and b.bundled_item.tax_rule_id != self.item.tax_rule_id:
                     if b.bundled_variation:
-                        bprice = b.bundled_variation.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
+                        bprice = b.bundled_variation.tax(b.designated_price * b.count, base_price_is='gross',
+                                                         currency=currency,
+                                                         invoice_address=invoice_address)
                     else:
-                        bprice = b.bundled_item.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
-                    compare_price = self.item.tax_rule.tax(b.designated_price * b.count, base_price_is='gross', currency=currency)
+                        bprice = b.bundled_item.tax(b.designated_price * b.count, base_price_is='gross',
+                                                    currency=currency,
+                                                    invoice_address=invoice_address)
+                    compare_price = self.item.tax_rule.tax(b.designated_price * b.count, base_price_is='gross',
+                                                           currency=currency, invoice_address=invoice_address)
                     t.net += bprice.net - compare_price.net
                     t.tax += bprice.tax - compare_price.tax
                     t.name = "MIXED!"

src/pretix/base/models/orders.py

@@ -1813,13 +1813,9 @@ class OrderFee(models.Model):
             self.tax_rule = self.order.event.settings.tax_rate_default
 
         if self.tax_rule:
-            if self.tax_rule.tax_applicable(ia):
-                tax = self.tax_rule.tax(self.value, base_price_is='gross')
-                self.tax_rate = tax.rate
-                self.tax_value = tax.tax
-            else:
-                self.tax_value = Decimal('0.00')
-                self.tax_rate = Decimal('0.00')
+            tax = self.tax_rule.tax(self.value, base_price_is='gross', invoice_address=ia)
+            self.tax_rate = tax.rate
+            self.tax_value = tax.tax
         else:
             self.tax_value = Decimal('0.00')
             self.tax_rate = Decimal('0.00')
@@ -1966,13 +1962,9 @@ class OrderPosition(AbstractPosition):
         except InvoiceAddress.DoesNotExist:
             ia = None
         if self.tax_rule:
-            if self.tax_rule.tax_applicable(ia):
-                tax = self.tax_rule.tax(self.price, base_price_is='gross')
-                self.tax_rate = tax.rate
-                self.tax_value = tax.tax
-            else:
-                self.tax_value = Decimal('0.00')
-                self.tax_rate = Decimal('0.00')
+            tax = self.tax_rule.tax(self.price, invoice_address=ia, base_price_is='gross')
+            self.tax_rate = tax.rate
+            self.tax_value = tax.tax
         else:
             self.tax_value = Decimal('0.00')
             self.tax_rate = Decimal('0.00')
@@ -2111,6 +2103,10 @@ class CartPosition(AbstractPosition):
     includes_tax = models.BooleanField(
         default=True
     )
+    override_tax_rate = models.DecimalField(
+        max_digits=10, decimal_places=2,
+        null=True, blank=True
+    )
     is_bundled = models.BooleanField(default=False)
 
     objects = ScopedManager(organizer='event__organizer')
@@ -2127,6 +2123,8 @@ class CartPosition(AbstractPosition):
     @property
     def tax_rate(self):
         if self.includes_tax:
+            if self.override_tax_rate is not None:
+                return self.override_tax_rate
             return self.item.tax(self.price, base_price_is='gross').rate
         else:
             return Decimal('0.00')
@@ -2134,7 +2132,7 @@ class CartPosition(AbstractPosition):
     @property
     def tax_value(self):
         if self.includes_tax:
-            return self.item.tax(self.price, base_price_is='gross').tax
+            return self.item.tax(self.price, override_tax_rate=self.override_tax_rate, base_price_is='gross').tax
         else:
             return Decimal('0.00')
 

src/pretix/base/models/tax.py

@@ -164,16 +164,39 @@ class TaxRule(LoggedModel):
     def has_custom_rules(self):
         return self.custom_rules and self.custom_rules != '[]'
 
-    def tax(self, base_price, base_price_is='auto', currency=None):
+    def tax_rate_for(self, invoice_address):
+        if not self._tax_applicable(invoice_address):
+            return Decimal('0.00')
+        if self.has_custom_rules:
+            rule = self.get_matching_rule(invoice_address)
+            if rule.get('action', 'vat') == 'vat' and rule.get('rate') is not None:
+                return Decimal(rule.get('rate'))
+        return Decimal(self.rate)
+
+    def tax(self, base_price, base_price_is='auto', currency=None, override_tax_rate=None, invoice_address=None,
+            subtract_from_gross=Decimal('0.00')):
         from .event import Event
         try:
             currency = currency or self.event.currency
         except Event.DoesNotExist:
             pass
-        if self.rate == Decimal('0.00'):
+
+        rate = Decimal(self.rate)
+        if override_tax_rate is not None:
+            rate = override_tax_rate
+        elif invoice_address:
+            adjust_rate = self.tax_rate_for(invoice_address)
+            if adjust_rate != rate:
+                normal_price = self.tax(base_price, base_price_is, currency, subtract_from_gross=subtract_from_gross)
+                base_price = normal_price.net
+                base_price_is = 'net'
+                subtract_from_gross = Decimal('0.00')
+                rate = adjust_rate
+
+        if rate == Decimal('0.00'):
             return TaxedPrice(
-                net=base_price, gross=base_price, tax=Decimal('0.00'),
-                rate=self.rate, name=self.name
+                net=base_price - subtract_from_gross, gross=base_price - subtract_from_gross, tax=Decimal('0.00'),
+                rate=rate, name=self.name
             )
 
         if base_price_is == 'auto':
@@ -183,19 +206,22 @@ class TaxRule(LoggedModel):
                 base_price_is = 'net'
 
         if base_price_is == 'gross':
-            gross = base_price
-            net = round_decimal(gross - (base_price * (1 - 100 / (100 + self.rate))),
+            gross = max(Decimal('0.00'), base_price - subtract_from_gross)
+            net = round_decimal(gross - (gross * (1 - 100 / (100 + rate))),
                                 currency)
         elif base_price_is == 'net':
             net = base_price
-            gross = round_decimal((net * (1 + self.rate / 100)),
-                                  currency)
+            gross = round_decimal((net * (1 + rate / 100)), currency)
+            if subtract_from_gross:
+                gross -= subtract_from_gross
+                net = round_decimal(gross - (gross * (1 - 100 / (100 + rate))),
+                                    currency)
         else:
             raise ValueError('Unknown base price type: {}'.format(base_price_is))
 
         return TaxedPrice(
             net=net, gross=gross, tax=gross - net,
-            rate=self.rate, name=self.name
+            rate=rate, name=self.name
         )
 
     @property
@@ -243,7 +269,7 @@ class TaxRule(LoggedModel):
 
         return False
 
-    def tax_applicable(self, invoice_address):
+    def _tax_applicable(self, invoice_address):
         if self._custom_rules:
             rule = self.get_matching_rule(invoice_address)
             return rule.get('action', 'vat') == 'vat'

src/pretix/base/services/cart.py

@@ -907,6 +907,7 @@ class CartManager:
                             price=op.price.gross, expires=self._expiry, cart_id=self.cart_id,
                             voucher=op.voucher, addon_to=op.addon_to if op.addon_to else None,
                             subevent=op.subevent, includes_tax=op.includes_tax, seat=op.seat,
+                            override_tax_rate=op.price.rate,
                             price_before_voucher=op.price_before_voucher.gross if op.price_before_voucher is not None else None
                         )
                         if self.event.settings.attendee_names_asked:
@@ -940,7 +941,7 @@ class CartManager:
                                     new_cart_positions.append(CartPosition(
                                         event=self.event, item=b.item, variation=b.variation,
                                         price=b.price.gross, expires=self._expiry, cart_id=self.cart_id,
-                                        voucher=None, addon_to=cp,
+                                        voucher=None, addon_to=cp, override_tax_rate=b.price.rate,
                                         subevent=b.subevent, includes_tax=b.includes_tax, is_bundled=True
                                     ))
 
@@ -1032,19 +1033,15 @@ def update_tax_rates(event: Event, cart_id: str, invoice_address: InvoiceAddress
     for pos in positions:
         if not pos.item.tax_rule:
             continue
-        charge_tax = pos.item.tax_rule.tax_applicable(invoice_address)
-        if pos.includes_tax and not charge_tax:
-            price = pos.item.tax(pos.price, base_price_is='gross').net
-            totaldiff += price - pos.price
-            pos.price = price
-            pos.includes_tax = False
-            pos.save(update_fields=['price', 'includes_tax'])
-        elif charge_tax and not pos.includes_tax:
-            price = pos.item.tax(pos.price, base_price_is='net').gross
-            totaldiff += price - pos.price
-            pos.price = price
-            pos.includes_tax = True
-            pos.save(update_fields=['price', 'includes_tax'])
+        rate = pos.item.tax_rule.tax_rate_for(invoice_address)
+
+        if pos.tax_rate != rate:
+            current_net = pos.price - pos.tax_value
+            new_gross = pos.item.tax(current_net, base_price_is='net', invoice_address=invoice_address).gross
+            pos.price = new_gross
+            pos.includes_tax = rate != Decimal('0.00')
+            pos.override_tax_rate = rate
+            pos.save(update_fields=['price', 'includes_tax', 'override_tax_rate'])
 
     return totaldiff
 
@@ -1092,23 +1089,14 @@ def get_fees(event, request, total, invoice_address, provider, positions):
 
             if payment_fee:
                 payment_fee_tax_rule = event.settings.tax_rate_default or TaxRule.zero()
-                if payment_fee_tax_rule.tax_applicable(invoice_address):
-                    payment_fee_tax = payment_fee_tax_rule.tax(payment_fee, base_price_is='gross')
-                    fees.append(OrderFee(
-                        fee_type=OrderFee.FEE_TYPE_PAYMENT,
-                        value=payment_fee,
-                        tax_rate=payment_fee_tax.rate,
-                        tax_value=payment_fee_tax.tax,
-                        tax_rule=payment_fee_tax_rule
-                    ))
-                else:
-                    fees.append(OrderFee(
-                        fee_type=OrderFee.FEE_TYPE_PAYMENT,
-                        value=payment_fee,
-                        tax_rate=Decimal('0.00'),
-                        tax_value=Decimal('0.00'),
-                        tax_rule=payment_fee_tax_rule
-                    ))
+                payment_fee_tax = payment_fee_tax_rule.tax(payment_fee, base_price_is='gross', invoice_address=invoice_address)
+                fees.append(OrderFee(
+                    fee_type=OrderFee.FEE_TYPE_PAYMENT,
+                    value=payment_fee,
+                    tax_rate=payment_fee_tax.rate,
+                    tax_value=payment_fee_tax.tax,
+                    tax_rule=payment_fee_tax_rule
+                ))
 
     return fees
 

src/pretix/base/services/invoices.py

@@ -24,7 +24,7 @@ from pretix.base.i18n import language
 from pretix.base.models import (
     Invoice, InvoiceAddress, InvoiceLine, Order, OrderFee,
 )
-from pretix.base.models.tax import EU_CURRENCIES
+from pretix.base.models.tax import EU_COUNTRIES, EU_CURRENCIES
 from pretix.base.services.tasks import TransactionAwareTask
 from pretix.base.settings import GlobalSettingsObject
 from pretix.base.signals import invoice_line_text, periodic_task
@@ -181,11 +181,17 @@ def build_invoice(invoice: Invoice) -> Invoice:
         if reverse_charge:
             if invoice.additional_text:
                 invoice.additional_text += "<br /><br />"
-            invoice.additional_text += pgettext(
-                "invoice",
-                "Reverse Charge: According to Article 194, 196 of Council Directive 2006/112/EEC, VAT liability "
-                "rests with the service recipient."
-            )
+            if str(invoice.invoice_to_country) in EU_COUNTRIES:
+                invoice.additional_text += pgettext(
+                    "invoice",
+                    "Reverse Charge: According to Article 194, 196 of Council Directive 2006/112/EEC, VAT liability "
+                    "rests with the service recipient."
+                )
+            else:
+                invoice.additional_text += pgettext(
+                    "invoice",
+                    "VAT liability rests with the service recipient."
+                )
             invoice.reverse_charge = True
             invoice.save()
 

src/pretix/base/services/orders.py

@@ -34,7 +34,7 @@ from pretix.base.models.orders import (
     generate_secret,
 )
 from pretix.base.models.organizer import TeamAPIToken
-from pretix.base.models.tax import TaxedPrice, TaxRule
+from pretix.base.models.tax import TaxRule
 from pretix.base.payment import BasePaymentProvider, PaymentException
 from pretix.base.reldate import RelativeDateWrapper
 from pretix.base.services import tickets
@@ -1263,7 +1263,8 @@ class OrderChangeManager:
         self._operations.append(self.RegenerateSecretOperation(position))
 
     def change_price(self, position: OrderPosition, price: Decimal):
-        price = position.item.tax(price, base_price_is='gross')
+        tax_rule = self._current_tax_rules().get(position.pk, position.tax_rule)
+        price = tax_rule.tax(price, base_price_is='gross')
 
         if position.issued_gift_cards.exists():
             raise OrderError(self.error_messages['gift_card_change'])
@@ -1279,27 +1280,38 @@ class OrderChangeManager:
         self._operations.append(self.TaxRuleOperation(position_or_fee, tax_rule))
         self._invoice_dirty = True
 
-    def recalculate_taxes(self):
+    def _current_tax_rules(self):
+        tax_rules = {}
+        for p in self._operations:
+            if isinstance(p, self.TaxRuleOperation):
+                tax_rules[p.position.pk] = p.tax_rule
+            elif isinstance(p, self.ItemOperation):
+                tax_rules[p.position.pk] = p.item.tax_rule
+        return tax_rules
+
+    def recalculate_taxes(self, keep='net'):
         positions = self.order.positions.select_related('item', 'item__tax_rule')
         ia = self._invoice_address
+        tax_rules = self._current_tax_rules()
+
         for pos in positions:
-            if not pos.item.tax_rule:
+            tax_rule = tax_rules.get(pos.pk, pos.tax_rule)
+            if not tax_rule:
                 continue
             if not pos.price:
                 continue
 
-            charge_tax = pos.item.tax_rule.tax_applicable(ia)
-            if pos.tax_value and not charge_tax:
-                net_price = pos.price - pos.tax_value
-                price = TaxedPrice(gross=net_price, net=net_price, tax=Decimal('0.00'), rate=Decimal('0.00'), name='')
-                if price.gross != pos.price:
-                    self._totaldiff += price.gross - pos.price
-                    self._operations.append(self.PriceOperation(pos, price))
-            elif charge_tax and not pos.tax_value:
-                price = pos.item.tax(pos.price, base_price_is='net')
-                if price.gross != pos.price:
-                    self._totaldiff += price.gross - pos.price
-                    self._operations.append(self.PriceOperation(pos, price))
+            new_rate = tax_rule.tax_rate_for(ia)
+            # We use override_tax_rate to make sure .tax() doesn't get clever and re-adjusts the pricing itself
+            if new_rate != pos.tax_rate:
+                if keep == 'net':
+                    new_tax = tax_rule.tax(pos.price - pos.tax_value, base_price_is='net', currency=self.event.currency,
+                                           override_tax_rate=new_rate)
+                else:
+                    new_tax = tax_rule.tax(pos.price, base_price_is='gross', currency=self.event.currency,
+                                           override_tax_rate=new_rate)
+                self._totaldiff += new_tax.gross - pos.price
+                self._operations.append(self.PriceOperation(pos, new_tax))
 
     def cancel_fee(self, fee: OrderFee):
         self._totaldiff -= fee.value
@@ -1345,10 +1357,7 @@ class OrderChangeManager:
         if price is None:
             price = get_price(item, variation, subevent=subevent, invoice_address=self._invoice_address)
         else:
-            if item.tax_rule and item.tax_rule.tax_applicable(self._invoice_address):
-                price = item.tax(price, base_price_is='gross')
-            else:
-                price = TaxedPrice(gross=price, net=price, tax=Decimal('0.00'), rate=Decimal('0.00'), name='')
+            price = item.tax(price, base_price_is='gross', invoice_address=self._invoice_address)
 
         if price is None:
             raise OrderError(self.error_messages['product_invalid'])
@@ -1599,7 +1608,8 @@ class OrderChangeManager:
                     'new_price': op.price.gross
                 })
                 op.position.price = op.price.gross
-                op.position._calculate_tax()
+                op.position.tax_rate = op.price.rate
+                op.position.tax_value = op.price.tax
                 op.position.save()
             elif isinstance(op, self.TaxRuleOperation):
                 if isinstance(op.position, OrderPosition):

src/pretix/base/services/pricing.py

@@ -46,33 +46,27 @@ def get_price(item: Item, variation: ItemVariation = None,
             price_includes_tax=True,
             eu_reverse_charge=False,
         )
-    price = tax_rule.tax(price)
+
+    price = tax_rule.tax(price, invoice_address=invoice_address, subtract_from_gross=bundled_sum)
 
     if force_custom_price and custom_price is not None and custom_price != "":
         if custom_price_is_net:
-            price = tax_rule.tax(custom_price, base_price_is='net')
+            price = tax_rule.tax(custom_price, base_price_is='net', invoice_address=invoice_address,
+                                 subtract_from_gross=bundled_sum)
         else:
-            price = tax_rule.tax(custom_price, base_price_is='gross')
+            price = tax_rule.tax(custom_price, base_price_is='gross', invoice_address=invoice_address,
+                                 subtract_from_gross=bundled_sum)
     if item.free_price and custom_price is not None and custom_price != "":
         if not isinstance(custom_price, Decimal):
             custom_price = Decimal(str(custom_price).replace(",", "."))
         if custom_price > 100000000:
             raise ValueError('price_too_high')
         if custom_price_is_net:
-            price = tax_rule.tax(max(custom_price, price.net), base_price_is='net')
+            price = tax_rule.tax(max(custom_price, price.net), base_price_is='net',
+                                 invoice_address=invoice_address, subtract_from_gross=bundled_sum)
         else:
-            price = tax_rule.tax(max(custom_price, price.gross), base_price_is='gross')
-
-    if bundled_sum:
-        price = price - TaxedPrice(net=bundled_sum, gross=bundled_sum, rate=0, tax=0, name='')
-        if price.gross < Decimal('0.00'):
-            return TAXED_ZERO
-
-    if invoice_address and not tax_rule.tax_applicable(invoice_address):
-        price.tax = Decimal('0.00')
-        price.rate = Decimal('0.00')
-        price.gross = price.net
-        price.name = ''
+            price = tax_rule.tax(max(custom_price, price.gross), base_price_is='gross',
+                                 invoice_address=invoice_address, subtract_from_gross=bundled_sum)
 
     price.gross = round_decimal(price.gross, item.event.currency)
     price.net = round_decimal(price.net, item.event.currency)

src/pretix/control/forms/event.py

@@ -1086,6 +1086,11 @@ class TaxRuleLineForm(forms.Form):
             ('no', _('No VAT')),
         ],
     )
+    rate = forms.DecimalField(
+        label=_('Deviating tax rate'),
+        max_digits=10, decimal_places=2,
+        required=False
+    )
 
 
 TaxRuleLineFormSet = formset_factory(

src/pretix/control/forms/orders.py

@@ -183,14 +183,15 @@ class CommentForm(I18nModelForm):
 
 
 class OtherOperationsForm(forms.Form):
-    recalculate_taxes = forms.BooleanField(
+    recalculate_taxes = forms.ChoiceField(
         label=_('Re-calculate taxes'),
         required=False,
-        help_text=_(
-            'This operation re-checks if taxes should be paid to the items due to e.g. configured reverse charge rules '
-            'and changes the prices and tax values accordingly. This is useful e.g. after an invoice address change. '
-            'Use with care and only if you need to. Note that rounding differences might occur in this procedure.'
-        )
+        choices=(
+            ('', _('Do not re-calculate taxes')),
+            ('gross', _('Re-calculate taxes based on address and product settings, keep gross amount the same.')),
+            ('net', _('Re-calculate taxes based on address and product settings, keep net amount the same.')),
+        ),
+        widget=forms.RadioSelect
     )
     reissue_invoice = forms.BooleanField(
         label=_('Issue a new invoice if required'),

src/pretix/control/templates/pretixcontrol/event/tax_edit.html

@@ -59,7 +59,7 @@
                                     {{ form.id }}
                                     {% bootstrap_field form.DELETE form_group_class="" layout="inline" %}
                                 </div>
-                                <div class="col-sm-4">
+                                <div class="col-sm-3">
                                     {% bootstrap_field form.country layout='inline' form_group_class="" %}
                                 </div>
                                 <div class="col-sm-3">
@@ -68,8 +68,11 @@
                                 <div class="col-sm-3">
                                     {% bootstrap_field form.action layout='inline' form_group_class="" %}
                                 </div>
-                                <div class="col-sm-2 text-right flip">
-                                    <button type="button" class="btn btn-danger" data-formset-delete-button>
+                                <div class="col-sm-2">
+                                    {% bootstrap_field form.rate layout='inline' form_group_class="" %}
+                                </div>
+                                <div class="col-sm-1 text-right flip">
+                                    <button type="button" class="btn btn-block btn-danger" data-formset-delete-button>
                                         <i class="fa fa-trash"></i></button>
                                 </div>
                             </div>
@@ -82,7 +85,7 @@
                                     {{ form.id }}
                                     {% bootstrap_field formset.empty_form.DELETE form_group_class="" layout="inline" %}
                                 </div>
-                                <div class="col-sm-4">
+                                <div class="col-sm-3">
                                     {% bootstrap_field formset.empty_form.country layout='inline' form_group_class="" %}
                                 </div>
                                 <div class="col-sm-3">
@@ -91,8 +94,11 @@
                                 <div class="col-sm-3">
                                     {% bootstrap_field formset.empty_form.action layout='inline' form_group_class="" %}
                                 </div>
-                                <div class="col-sm-2 text-right flip">
-                                    <button type="button" class="btn btn-danger" data-formset-delete-button>
+                                <div class="col-sm-2">
+                                    {% bootstrap_field formset.empty_form.rate layout='inline' form_group_class="" %}
+                                </div>
+                                <div class="col-sm-1 text-right flip">
+                                    <button type="button" class="btn btn-block btn-danger" data-formset-delete-button>
                                         <i class="fa fa-trash"></i></button>
                                 </div>
                             </div>

src/pretix/control/views/event.py

@@ -9,6 +9,7 @@ from django.conf import settings
 from django.contrib import messages
 from django.contrib.contenttypes.models import ContentType
 from django.core.files import File
+from django.core.serializers.json import DjangoJSONEncoder
 from django.db import transaction
 from django.db.models import ProtectedError
 from django.forms import inlineformset_factory
@@ -1135,7 +1136,7 @@ class TaxUpdate(EventSettingsViewMixin, EventPermissionRequiredMixin, UpdateView
         messages.success(self.request, _('Your changes have been saved.'))
         form.instance.custom_rules = json.dumps([
             f.cleaned_data for f in self.formset if f not in self.formset.deleted_forms
-        ])
+        ], cls=DjangoJSONEncoder)
         if form.has_changed():
             self.object.log_action(
                 'pretix.event.taxrule.changed', user=self.request.user, data={

src/pretix/control/views/orders.py

@@ -1397,11 +1397,6 @@ class OrderChange(OrderView):
         for f in fees:
             f.form = OrderFeeChangeForm(prefix='of-{}'.format(f.pk), instance=f,
                                         data=self.request.POST if self.request.method == "POST" else None)
-            try:
-                ia = self.order.invoice_address
-            except InvoiceAddress.DoesNotExist:
-                ia = None
-            f.apply_tax = self.request.event.settings.tax_rate_default and self.request.event.settings.tax_rate_default.tax_applicable(invoice_address=ia)
         return fees
 
     @cached_property
@@ -1411,11 +1406,6 @@ class OrderChange(OrderView):
             p.form = OrderPositionChangeForm(prefix='op-{}'.format(p.pk), instance=p, items=self.items,
                                              initial={'seat': p.seat.seat_guid if p.seat else None},
                                              data=self.request.POST if self.request.method == "POST" else None)
-            try:
-                ia = self.order.invoice_address
-            except InvoiceAddress.DoesNotExist:
-                ia = None
-            p.apply_tax = p.item.tax_rule and p.item.tax_rule.tax_applicable(invoice_address=ia)
         return positions
 
     def get_context_data(self, **kwargs):
@@ -1431,7 +1421,9 @@ class OrderChange(OrderView):
             return False
         else:
             if self.other_form.cleaned_data['recalculate_taxes']:
-                ocm.recalculate_taxes()
+                ocm.recalculate_taxes(
+                    keep=self.other_form.cleaned_data['recalculate_taxes']
+                )
             return True
 
     def _process_add(self, ocm):
@@ -1523,7 +1515,7 @@ class OrderChange(OrderView):
                 if p.seat and p.form.cleaned_data['seat'] and p.form.cleaned_data['seat'] != p.seat.seat_guid:
                     ocm.change_seat(p, p.form.cleaned_data['seat'])
 
-                if p.form.cleaned_data['price'] != p.price:
+                if p.form.cleaned_data['price'] is not None and p.form.cleaned_data['price'] != p.price:
                     ocm.change_price(p, p.form.cleaned_data['price'])
 
                 if p.form.cleaned_data['tax_rule'] and p.form.cleaned_data['tax_rule'] != p.tax_rule: