diff --git a/sdk/cosmos/azure-cosmos/CHANGELOG.md b/sdk/cosmos/azure-cosmos/CHANGELOG.md
index 88216cd2235f..e8abbd59d18c 100644
--- a/sdk/cosmos/azure-cosmos/CHANGELOG.md
+++ b/sdk/cosmos/azure-cosmos/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ### 4.3.0b5 (Unreleased)
 
+#### Breaking Changes
+- Bugfix: Automatic Id generation for items was turned on for `upsert_items()` method when no 'id' value was present in document body.
+Method call will now require an 'id' field to be present in the document body.
+
 #### Other Changes
 - Marked the GetAuthorizationMethod for deprecation since it will no longer be public in a future release.
 - Added samples showing how to configure retry options for both the sync and async clients.
diff --git a/sdk/cosmos/azure-cosmos/azure/cosmos/aio/container.py b/sdk/cosmos/azure-cosmos/azure/cosmos/aio/container.py
index 50c47c4026fd..58c67b07d7c6 100644
--- a/sdk/cosmos/azure-cosmos/azure/cosmos/aio/container.py
+++ b/sdk/cosmos/azure-cosmos/azure/cosmos/aio/container.py
@@ -445,7 +445,7 @@ async def upsert_item(
         """
         request_options = _build_options(kwargs)
         response_hook = kwargs.pop('response_hook', None)
-        request_options["disableIdGeneration"] = True
+        request_options["disableAutomaticIdGeneration"] = True
         if pre_trigger_include is not None:
             request_options["preTriggerInclude"] = pre_trigger_include
         if post_trigger_include is not None:
@@ -492,7 +492,7 @@ async def replace_item(
         item_link = self._get_document_link(item)
         request_options = _build_options(kwargs)
         response_hook = kwargs.pop('response_hook', None)
-        request_options["disableIdGeneration"] = True
+        request_options["disableAutomaticIdGeneration"] = True
         if pre_trigger_include is not None:
             request_options["preTriggerInclude"] = pre_trigger_include
         if post_trigger_include is not None:
diff --git a/sdk/cosmos/azure-cosmos/azure/cosmos/container.py b/sdk/cosmos/azure-cosmos/azure/cosmos/container.py
index 1658f6e957d4..9f075eba64d5 100644
--- a/sdk/cosmos/azure-cosmos/azure/cosmos/container.py
+++ b/sdk/cosmos/azure-cosmos/azure/cosmos/container.py
@@ -426,7 +426,7 @@ def replace_item(
         item_link = self._get_document_link(item)
         request_options = build_options(kwargs)
         response_hook = kwargs.pop('response_hook', None)
-        request_options["disableIdGeneration"] = True
+        request_options["disableAutomaticIdGeneration"] = True
         if populate_query_metrics is not None:
             request_options["populateQueryMetrics"] = populate_query_metrics
         if pre_trigger_include is not None:
@@ -472,7 +472,7 @@ def upsert_item(
         """
         request_options = build_options(kwargs)
         response_hook = kwargs.pop('response_hook', None)
-        request_options["disableIdGeneration"] = True
+        request_options["disableAutomaticIdGeneration"] = True
         if populate_query_metrics is not None:
             request_options["populateQueryMetrics"] = populate_query_metrics
         if pre_trigger_include is not None: