diff --git a/sdk/eventhub/azure-eventhub/tests/unittest/test_event_data.py b/sdk/eventhub/azure-eventhub/tests/unittest/test_event_data.py
index 50502563681c..f32cec472067 100644
--- a/sdk/eventhub/azure-eventhub/tests/unittest/test_event_data.py
+++ b/sdk/eventhub/azure-eventhub/tests/unittest/test_event_data.py
@@ -93,6 +93,6 @@ def test_event_data_batch():
     batch.add(EventData("A"))
     assert str(batch) == "EventDataBatch(max_size_in_bytes=100, partition_id=None, partition_key='par', event_count=1)"
     assert repr(batch) == "EventDataBatch(max_size_in_bytes=100, partition_id=None, partition_key='par', event_count=1)"
-    assert batch.size_in_bytes == 89 and len(batch) == 1
+    assert batch.size_in_bytes == 97 and len(batch) == 1
     with pytest.raises(ValueError):
         batch.add(EventData("A"))