diff --git a/pandas/core/generic.py b/pandas/core/generic.py
index c893e9ce3d9a9..7e8196c9b27f3 100644
--- a/pandas/core/generic.py
+++ b/pandas/core/generic.py
@@ -10099,7 +10099,7 @@ def truncate(
     @final
     @doc(klass=_shared_doc_kwargs["klass"])
     def tz_convert(
-        self: NDFrameT, tz, axis: Axis = 0, level=None, copy: bool_t = True
+        self: NDFrameT, tz, axis: Axis = 0, level=None, copy: bool_t | None = None
     ) -> NDFrameT:
         """
         Convert tz-aware axis to target time zone.
@@ -10181,7 +10181,7 @@ def tz_localize(
         tz,
         axis: Axis = 0,
         level=None,
-        copy: bool_t = True,
+        copy: bool_t | None = None,
         ambiguous: TimeAmbiguous = "raise",
         nonexistent: TimeNonexistent = "raise",
     ) -> NDFrameT:
diff --git a/pandas/tests/copy_view/test_methods.py b/pandas/tests/copy_view/test_methods.py
index 878f1d8089d33..d819e806516ad 100644
--- a/pandas/tests/copy_view/test_methods.py
+++ b/pandas/tests/copy_view/test_methods.py
@@ -5,6 +5,7 @@
     DataFrame,
     MultiIndex,
     Series,
+    date_range,
 )
 import pandas._testing as tm
 from pandas.tests.copy_view.util import get_array
@@ -441,6 +442,28 @@ def test_frame_set_axis(using_copy_on_write):
     tm.assert_frame_equal(df, df_orig)
 
 
+@pytest.mark.parametrize(
+    "func, tz", [("tz_convert", "Europe/Berlin"), ("tz_localize", None)]
+)
+def test_tz_convert_localize(using_copy_on_write, func, tz):
+    # GH 49473
+    ser = Series(
+        [1, 2], index=date_range(start="2014-08-01 09:00", freq="H", periods=2, tz=tz)
+    )
+    ser_orig = ser.copy()
+    ser2 = getattr(ser, func)("US/Central")
+
+    if using_copy_on_write:
+        assert np.shares_memory(ser.values, ser2.values)
+    else:
+        assert not np.shares_memory(ser.values, ser2.values)
+
+    # mutating ser triggers a copy-on-write for the column / block
+    ser2.iloc[0] = 0
+    assert not np.shares_memory(ser2.values, ser.values)
+    tm.assert_series_equal(ser, ser_orig)
+
+
 def test_series_set_axis(using_copy_on_write):
     # GH 49473
     ser = Series([1, 2, 3])