diff --git a/src/mkdocstrings/handlers/base.py b/src/mkdocstrings/handlers/base.py
index 24eaa4d2..a8de29ac 100644
--- a/src/mkdocstrings/handlers/base.py
+++ b/src/mkdocstrings/handlers/base.py
@@ -571,8 +571,9 @@ def get_handler(self, name: str, handler_config: Optional[dict] = None) -> BaseH
                         )
                     )
             self._handlers[name] = module.get_handler(
-                self._config["theme_name"],
-                self._config["mkdocstrings"]["custom_templates"],
+                theme=self._config["theme_name"],
+                custom_templates=self._config["mkdocstrings"]["custom_templates"],
+                config_file_path=self._config["config_file_path"],
                 **handler_config,
             )
         return self._handlers[name]
diff --git a/src/mkdocstrings/plugin.py b/src/mkdocstrings/plugin.py
index 4f2fdda6..fd47291a 100644
--- a/src/mkdocstrings/plugin.py
+++ b/src/mkdocstrings/plugin.py
@@ -166,6 +166,7 @@ def on_config(self, config: Config, **kwargs: Any) -> Config:  # noqa: W0613 (un
 
         extension_config = {
             "site_name": config["site_name"],
+            "config_file_path": config["config_file_path"],
             "theme_name": theme_name,
             "mdx": config["markdown_extensions"],
             "mdx_configs": config["mdx_configs"],