diff --git a/async_substrate_interface/sync_substrate.py b/async_substrate_interface/sync_substrate.py
index 8bb5211..f6cb4e1 100644
--- a/async_substrate_interface/sync_substrate.py
+++ b/async_substrate_interface/sync_substrate.py
@@ -525,6 +525,9 @@ def __enter__(self):
         self.initialize()
         return self
 
+    def __del__(self):
+        self.close()
+
     def initialize(self):
         """
         Initialize the connection to the chain.