diff --git a/src/pretix/base/models/items.py b/src/pretix/base/models/items.py
index f2dc8ec76b..aa4f6f9c2e 100644
--- a/src/pretix/base/models/items.py
+++ b/src/pretix/base/models/items.py
@@ -164,54 +164,55 @@ class ItemCategory(LoggedModel):
             match = set(match.pk for match in self.cross_selling_match_products.only('pk'))  # TODO prefetch this
             return (self.items.all(), {}) if any(pos.item.pk in match for pos in cart) else (None, {})
         if self.cross_selling_condition == 'discounts':
-            potential_discounts_by_cartpos = defaultdict(list)
+            if not hasattr(self.event, '_potential_discounts_by_item_for_current_cart'):
+                potential_discounts_by_cartpos = defaultdict(list)
 
-            from ..services.pricing import apply_discounts
-            apply_discounts(
-                self.event,
-                sales_channel,
-                [
-                    (cp.item_id, cp.subevent_id, cp.line_price_gross, bool(cp.addon_to), cp.is_bundled,
-                     cp.listed_price - cp.price_after_voucher)
-                    for cp in cart
-                ],
-                collect_potential_discounts=potential_discounts_by_cartpos
-            )
-
-            # technically, this is a dict, but we use it as an OrderedSet here
-            potential_discount_set = dict.fromkeys(info for lst in potential_discounts_by_cartpos.values() for info in lst)
-
-            # sum up the max_counts and pass them on (also pass on the discount_rules so we can calculate actual discounted prices later):
-            # group by benefit product
-            # - max_count for product: sum up max_counts
-            # - discount_rule for product: take first discount_rule
-
-            def discount_info(item, infos_for_item):
-                infos_for_item = list(infos_for_item)
-                return (
-                    item,
-                    sum(max_count for (item, discount_rule, max_count, i) in infos_for_item),
-                    next(discount_rule for (item, discount_rule, max_count, i) in infos_for_item)
+                from ..services.pricing import apply_discounts
+                apply_discounts(
+                    self.event,
+                    sales_channel,
+                    [
+                        (cp.item_id, cp.subevent_id, cp.line_price_gross, bool(cp.addon_to), cp.is_bundled,
+                         cp.listed_price - cp.price_after_voucher)
+                        for cp in cart
+                    ],
+                    collect_potential_discounts=potential_discounts_by_cartpos
                 )
 
-            grouped_by_item = [
-                discount_info(item, infos_for_item) for item, infos_for_item in
-                groupby(
-                    sorted(
-                        (
-                            (item, discount_rule, max_count, i)
-                            for (discount_rule, max_count, i) in potential_discount_set.keys()
-                            for item in discount_rule.benefit_limit_products.all()
+                # technically, this is a dict, but we use it as an OrderedSet here
+                potential_discount_set = dict.fromkeys(info for lst in potential_discounts_by_cartpos.values() for info in lst)
+
+                # sum up the max_counts and pass them on (also pass on the discount_rules so we can calculate actual discounted prices later):
+                # group by benefit product
+                # - max_count for product: sum up max_counts
+                # - discount_rule for product: take first discount_rule
+
+                def discount_info(item, infos_for_item):
+                    infos_for_item = list(infos_for_item)
+                    return (
+                        item,
+                        sum(max_count for (item, discount_rule, max_count, i) in infos_for_item),
+                        next(discount_rule for (item, discount_rule, max_count, i) in infos_for_item)
+                    )
+
+                self.event._potential_discounts_by_item_for_current_cart = [
+                    discount_info(item, infos_for_item) for item, infos_for_item in
+                    groupby(
+                        sorted(
+                            (
+                                (item, discount_rule, max_count, i)
+                                for (discount_rule, max_count, i) in potential_discount_set.keys()
+                                for item in discount_rule.benefit_limit_products.all()
+                            ),
+                            key=lambda tup: tup[0].pk
                         ),
-                        key=lambda tup: tup[0].pk
-                    ),
-                    lambda tup: tup[0])
-            ]
+                        lambda tup: tup[0])
+                ]
 
             my_item_pks = self.items.values_list('pk', flat=True)
             potential_discount_items = {
                 item.pk: (max_count, discount_rule)
-                for item, max_count, discount_rule in grouped_by_item
+                for item, max_count, discount_rule in self.event._potential_discounts_by_item_for_current_cart
                 if max_count > 0 and item.pk in my_item_pks and item.is_available()
             }