diff --git a/backend/order/signals.py b/backend/order/signals.py
index c157a1c..121ac35 100644
--- a/backend/order/signals.py
+++ b/backend/order/signals.py
@@ -112,9 +112,17 @@ def create_shop_orders_on_payment(sender, instance: OrderModel, created, **kwarg
             for it in items_list:
                 item_special_discounts += Decimal(str(it.special_discount_amount or 0))
             
-            # Proportionally allocate cart-level discount and tax
+            # Proportionally allocate cart-level discount
             allocated_discount = (Decimal(str(order_discount)) * Decimal(str(shop_subtotal)) / Decimal(str(total_subtotal))) if order_discount else Decimal('0')
-            allocated_tax = (Decimal(str(order_tax)) * Decimal(str(shop_subtotal)) / Decimal(str(total_subtotal))) if order_tax else Decimal('0')
+            
+            # Calculate tax on shop's amount after all discounts
+            # Tax rate from settings (default 10%)
+            tax_rate = Decimal(str(getattr(settings, 'DEFAULT_TAX_RATE', 10)))
+            base_for_tax = max(
+                Decimal('0'),
+                Decimal(str(shop_subtotal)) - item_level_discounts - item_special_discounts - allocated_discount
+            )
+            allocated_tax = base_for_tax * (tax_rate / Decimal('100'))
 
             commission_percent = getattr(shop, 'commission_percent', 0) or 0
             try: