diff --git a/pandas/tests/strings/conftest.py b/pandas/tests/strings/conftest.py
index 5bcbb16da3be9..122bebb517c9a 100644
--- a/pandas/tests/strings/conftest.py
+++ b/pandas/tests/strings/conftest.py
@@ -94,9 +94,10 @@
         ],
         [()] * 100,
         [{}] * 100,
+        strict=False,
     )
 )
-ids, _, _ = zip(*_any_string_method)  # use method name as fixture-id
+ids, _, _ = zip(*_any_string_method, strict=True)  # use method name as fixture-id
 missing_methods = {f for f in dir(StringMethods) if not f.startswith("_")} - set(ids)
 
 # test that the above list captures all methods of StringMethods
diff --git a/pandas/tests/strings/test_api.py b/pandas/tests/strings/test_api.py
index 6b9df072019eb..470ece15fa536 100644
--- a/pandas/tests/strings/test_api.py
+++ b/pandas/tests/strings/test_api.py
@@ -21,7 +21,7 @@
     ("empty", []),
     ("mixed-integer", ["a", np.nan, 2]),
 ]
-ids, _ = zip(*_any_allowed_skipna_inferred_dtype)  # use inferred type as id
+ids, _ = zip(*_any_allowed_skipna_inferred_dtype, strict=True)  # use inferred type as id
 
 
 @pytest.fixture(params=_any_allowed_skipna_inferred_dtype, ids=ids)
diff --git a/pandas/tests/strings/test_strings.py b/pandas/tests/strings/test_strings.py
index e07ece91090df..2ca5838283943 100644
--- a/pandas/tests/strings/test_strings.py
+++ b/pandas/tests/strings/test_strings.py
@@ -757,7 +757,7 @@ def test_cat_on_bytes_raises():
 
 def test_str_accessor_in_apply_func():
     # https://github.com/pandas-dev/pandas/issues/38979
-    df = DataFrame(zip("abc", "def"))
+    df = DataFrame(zip("abc", "def", strict=True))
     expected = Series(["A/D", "B/E", "C/F"])
     result = df.apply(lambda f: "/".join(f.str.upper()), axis=1)
     tm.assert_series_equal(result, expected)