diff --git a/csst_common/file.py b/csst_common/file.py
index 6d77d9d254e09545b98d4ac185d24f61693ca5a3..c81b966999d4ac451f4e6b130d13698048ed2c68 100644
--- a/csst_common/file.py
+++ b/csst_common/file.py
@@ -6,7 +6,7 @@ class File:
         self.file_path = file_path
         self.file_path_prefix, self.file_path_ext = os.path.splitext(file_path)
 
-    def switch_extension(self, ext="wht.fits") -> str:
+    def replace_ext(self, ext="wht.fits") -> str:
         if ext.startswith("."):
             return self.file_path_prefix + ext
         else:
diff --git a/tests/test_file.py b/tests/test_file.py
index 940557824d48a3758eb4eed1a1e6dc5ae2c8b90c..bc45a2d27e5c9364414f4e43c44105aa39c425ac 100644
--- a/tests/test_file.py
+++ b/tests/test_file.py
@@ -5,5 +5,5 @@ from csst_common import File
 class TestFile(unittest.TestCase):
     def test_parameterized_module_decorator(self):
         f = File("/path/to/file.fits")
-        self.assertEqual(f.switch_extension(".cat"), "/path/to/file.cat")
-        self.assertEqual(f.switch_extension("img.cat"), "/path/to/file_img.cat")
+        self.assertEqual(f.replace_ext(".cat"), "/path/to/file.cat")
+        self.assertEqual(f.replace_ext("img.cat"), "/path/to/file_img.cat")