diff --git a/CHANGES/5501.bugfix b/CHANGES/5501.bugfix
new file mode 100644
index 0000000000..33cdf5ef6f
--- /dev/null
+++ b/CHANGES/5501.bugfix
@@ -0,0 +1 @@
+Fixed content upload for existing on-demand content not properly storing the new artifact.
diff --git a/pulpcore/app/serializers/content.py b/pulpcore/app/serializers/content.py
index fcb62c80a8..907ca514cc 100644
--- a/pulpcore/app/serializers/content.py
+++ b/pulpcore/app/serializers/content.py
@@ -60,6 +60,7 @@ def create(self, validated_data):
         artifacts = self.get_artifacts(validated_data)
 
         content = self.retrieve(validated_data)
+        created = False
         if content is not None:
             content.touch()
         else:
@@ -74,6 +75,22 @@ def create(self, validated_data):
                 content = self.retrieve(validated_data)
                 if content is None:
                     raise
+            else:
+                created = True
+        # Ensure the content now has the uploaded artifact(s)
+        if not created:
+            ca_set = content.contentartifact_set
+            if ca_set.count() == 0 or ca_set.filter(artifact=None).exists():
+                cas = [
+                    models.ContentArtifact(artifact=a, content=content, relative_path=rp)
+                    for rp, a in artifacts.items()
+                ]
+                models.ContentArtifact.objects.bulk_create(
+                    cas,
+                    update_conflicts=True,
+                    update_fields=["artifact"],
+                    unique_fields=["content", "relative_path"],
+                )
 
         if repository:
             repository.cast()
diff --git a/pulpcore/tests/functional/api/using_plugin/test_content_access.py b/pulpcore/tests/functional/api/using_plugin/test_content_access.py
index d6c88fbe26..9029374865 100644
--- a/pulpcore/tests/functional/api/using_plugin/test_content_access.py
+++ b/pulpcore/tests/functional/api/using_plugin/test_content_access.py
@@ -40,3 +40,32 @@ def test_file_remote_on_demand(
     distribution = file_distribution_factory(repository=repo.pulp_href)
     # attempt to download_file() a file
     download_file(f"{distribution.base_url}/1.iso")
+
+
+@pytest.mark.parallel
+def test_upload_file_on_demand_already(
+    basic_manifest_path,
+    file_fixtures_root,
+    file_remote_factory,
+    file_repo,
+    file_bindings,
+    monitor_task,
+):
+    """Test that on-demand content can be uploaded to Pulp and become immediate content."""
+    remote = file_remote_factory(basic_manifest_path, policy="on_demand")
+    body = {"remote": remote.pulp_href}
+    monitor_task(file_bindings.RepositoriesFileApi.sync(file_repo.pulp_href, body).task)
+    file_repo = file_bindings.RepositoriesFileApi.read(file_repo.pulp_href)
+    result = file_bindings.ContentFilesApi.list(repository_version=file_repo.latest_version_href)
+    assert result.count == 3
+    for content in result.results:
+        assert content.artifact is None
+
+    file_content = file_fixtures_root / "basic" / content.relative_path
+    body = {"relative_path": content.relative_path, "file": file_content}
+    task = monitor_task(file_bindings.ContentFilesApi.create(**body).task)
+    assert len(task.created_resources) == 1
+    assert task.created_resources[0] == content.pulp_href
+
+    content = file_bindings.ContentFilesApi.read(content.pulp_href)
+    assert content.artifact is not None