diff --git a/dune_client/api/custom.py b/dune_client/api/custom.py
index bfd24ec..ce46060 100644
--- a/dune_client/api/custom.py
+++ b/dune_client/api/custom.py
@@ -5,6 +5,8 @@
 
 from __future__ import annotations
 
+from deprecated import deprecated
+
 from dune_client.api.base import BaseRouter
 from dune_client.models import (
     DuneError,
@@ -19,6 +21,10 @@ class CustomEndpointAPI(BaseRouter):
         get_custom_endpoint_result(): returns the results of a custom endpoint.
     """
 
+    @deprecated(
+        version="1.8.1",
+        reason="Custom endpoints feature is deprecated and will be removed in a future version",
+    )
     def get_custom_endpoint_result(
         self,
         handle: str,
diff --git a/tests/e2e/test_custom_endpoints.py b/tests/e2e/test_custom_endpoints.py
index eb56a89..375dc33 100644
--- a/tests/e2e/test_custom_endpoints.py
+++ b/tests/e2e/test_custom_endpoints.py
@@ -1,5 +1,6 @@
 import os
 import unittest
+import warnings
 
 import dotenv
 
@@ -15,8 +16,14 @@ def setUp(self) -> None:
 
     def test_getting_custom_endpoint_results(self):
         dune = DuneClient(self.valid_api_key)
-        results = dune.get_custom_endpoint_result("dune", "new-test")
-        assert len(results.get_rows()) == 10
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter("always")
+            results = dune.get_custom_endpoint_result("dune", "new-test")
+            assert len(results.get_rows()) == 10
+            # Verify that a deprecation warning was issued
+            assert len(w) == 1
+            assert issubclass(w[0].category, DeprecationWarning)
+            assert "deprecated" in str(w[0].message).lower()
 
 
 if __name__ == "__main__":