diff --git a/pandas/core/arrays/_mixins.py b/pandas/core/arrays/_mixins.py
index 6d21f4a1ac8a2..de2ae487c57ac 100644
--- a/pandas/core/arrays/_mixins.py
+++ b/pandas/core/arrays/_mixins.py
@@ -221,7 +221,7 @@ def unique(self) -> Self:
     def _concat_same_type(
         cls,
         to_concat: Sequence[Self],
-        axis: AxisInt = 0,
+        axis: AxisInt = 1,
     ) -> Self:
         if not lib.dtypes_all_equal([x.dtype for x in to_concat]):
             dtypes = {str(x.dtype) for x in to_concat}