diff --git a/deepeval/metrics/base_metric.py b/deepeval/metrics/base_metric.py
index a827ab18a..21e106bf5 100644
--- a/deepeval/metrics/base_metric.py
+++ b/deepeval/metrics/base_metric.py
@@ -16,7 +16,7 @@ class BaseMetric:
     verbose_mode: bool = True
     include_reason: bool = False
     error: Optional[str] = None
-    evaluation_cost: Optional[float] = None
+    evaluation_cost: Optional[float] = 0
     verbose_logs: Optional[str] = None
     skipped = False