diff --git a/src/backend/InvenTree/order/models.py b/src/backend/InvenTree/order/models.py
index 54e9aa422a86..456e70404cba 100644
--- a/src/backend/InvenTree/order/models.py
+++ b/src/backend/InvenTree/order/models.py
@@ -1098,6 +1098,8 @@ def _action_complete(self, *args, **kwargs):
             self.status = SalesOrderStatus.COMPLETE.value
         else:
             self.status = SalesOrderStatus.SHIPPED.value
+
+        if self.shipment_date is None:
             self.shipped_by = user
             self.shipment_date = InvenTree.helpers.current_date()
 
diff --git a/src/backend/InvenTree/order/test_api.py b/src/backend/InvenTree/order/test_api.py
index 4d8a78de8a80..7c77e9076a87 100644
--- a/src/backend/InvenTree/order/test_api.py
+++ b/src/backend/InvenTree/order/test_api.py
@@ -1576,6 +1576,8 @@ def test_sales_order_complete(self):
 
         so.refresh_from_db()
         self.assertEqual(so.status, SalesOrderStatus.SHIPPED.value)
+        self.assertIsNotNone(so.shipment_date)
+        self.assertIsNotNone(so.shipped_by)
 
         # Now, let's try to "complete" the shipment again
         # This time it should get marked as "COMPLETE"
@@ -1591,9 +1593,14 @@ def test_sales_order_complete(self):
 
         # Next, we'll change the setting so that the order status jumps straight to "complete"
         so.status = SalesOrderStatus.PENDING.value
+        so.shipment_date = None
+        so.shipped_by = None
         so.save()
         so.refresh_from_db()
+
         self.assertEqual(so.status, SalesOrderStatus.PENDING.value)
+        self.assertIsNone(so.shipped_by)
+        self.assertIsNone(so.shipment_date)
 
         InvenTreeSetting.set_setting('SALESORDER_SHIP_COMPLETE', True)
 
@@ -1603,6 +1610,9 @@ def test_sales_order_complete(self):
         so.refresh_from_db()
         self.assertEqual(so.status, SalesOrderStatus.COMPLETE.value)
 
+        self.assertIsNotNone(so.shipment_date)
+        self.assertIsNotNone(so.shipped_by)
+
 
 class SalesOrderLineItemTest(OrderTest):
     """Tests for the SalesOrderLineItem API."""