diff --git a/customerio/client_base.py b/customerio/client_base.py
index 60735d2..7a24ad4 100644
--- a/customerio/client_base.py
+++ b/customerio/client_base.py
@@ -101,7 +101,15 @@ def _build_session(self):
         # also define backoff_factor to delay each retry
         session.mount(
             'https://',
-            HTTPAdapter(max_retries=Retry(total=self.retries, backoff_factor=self.backoff_factor)))
+            HTTPAdapter(
+                max_retries=Retry(
+                    total=self.retries, 
+                    backoff_factor=self.backoff_factor,
+                    # Ensure POST methods get retries as well.
+                    allowed_methods=None
+                )
+            )
+        )
 
         return session