diff --git a/litellm/litellm_core_utils/get_model_cost_map.py b/litellm/litellm_core_utils/get_model_cost_map.py
index 81182f06dbf..b97cf32a67f 100644
--- a/litellm/litellm_core_utils/get_model_cost_map.py
+++ b/litellm/litellm_core_utils/get_model_cost_map.py
@@ -201,6 +201,13 @@ def _expand_model_aliases(model_cost: dict) -> dict:
         if aliases is None:
             continue
         keys_with_aliases.append(model_name)
+        if not isinstance(aliases, list):
+            verbose_logger.warning(
+                "LiteLLM model alias field for '%s' is not a list (got %s) — skipping.",
+                model_name,
+                type(aliases).__name__,
+            )
+            continue
         if not aliases:
             continue
         for alias in aliases:
diff --git a/tests/test_litellm/test_model_cost_aliases.py b/tests/test_litellm/test_model_cost_aliases.py
index ee01484922a..6e30cbfe157 100644
--- a/tests/test_litellm/test_model_cost_aliases.py
+++ b/tests/test_litellm/test_model_cost_aliases.py
@@ -7,19 +7,9 @@ entries, creating shared dict references for alias entries at load time.
 
 import logging
 
-
 from litellm.litellm_core_utils.get_model_cost_map import _expand_model_aliases
 
 
-# ---------------------------------------------------------------------------
-# Helpers
-# ---------------------------------------------------------------------------
-
-def _make_model_cost(**entries) -> dict:
-    """Build a small model_cost dict from keyword args (model_name → info)."""
-    return dict(entries)
-
-
 # ---------------------------------------------------------------------------
 # Core expansion behaviour
 # ---------------------------------------------------------------------------