diff --git a/pandas/tests/extension/decimal/test_decimal.py b/pandas/tests/extension/decimal/test_decimal.py
index c2e42ae2fe27e..acba1bd557351 100644
--- a/pandas/tests/extension/decimal/test_decimal.py
+++ b/pandas/tests/extension/decimal/test_decimal.py
@@ -284,6 +284,7 @@ def test_compare_array(self, data, comparison_op):
 class DecimalArrayWithoutFromSequence(DecimalArray):
     """Helper class for testing error handling in _from_sequence."""
 
+    @classmethod
     def _from_sequence(cls, scalars, dtype=None, copy=False):
         raise KeyError("For the test")
 
diff --git a/pandas/tests/io/test_sql.py b/pandas/tests/io/test_sql.py
index 1bfb85f369415..375f66d545ed4 100644
--- a/pandas/tests/io/test_sql.py
+++ b/pandas/tests/io/test_sql.py
@@ -1612,6 +1612,7 @@ class _TestSQLAlchemy(SQLAlchemyMixIn, PandasSQLTest):
 
     flavor: str
 
+    @classmethod
     @pytest.fixture(autouse=True, scope="class")
     def setup_class(cls):
         cls.setup_import()
diff --git a/pandas/tests/scalar/period/test_period.py b/pandas/tests/scalar/period/test_period.py
index c9e28f8249c1b..b5bd61854866d 100644
--- a/pandas/tests/scalar/period/test_period.py
+++ b/pandas/tests/scalar/period/test_period.py
@@ -840,6 +840,7 @@ def test_period_deprecated_freq(self):
             assert isinstance(p1, Period)
             assert isinstance(p2, Period)
 
+    @staticmethod
     def _period_constructor(bound, offset):
         return Period(
             year=bound.year,
diff --git a/pyproject.toml b/pyproject.toml
index 3e87d237170aa..02411464f5675 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -50,7 +50,6 @@ disable = [
   "no-member",
   "no-method-argument",
   "no-name-in-module",
-  "no-self-argument",
   "no-value-for-parameter",
   "non-iterator-returned",
   "not-an-iterable",