diff --git a/Tests/test_imagecms.py b/Tests/test_imagecms.py
index 7b8051486d4..c774bfc52cd 100644
--- a/Tests/test_imagecms.py
+++ b/Tests/test_imagecms.py
@@ -418,7 +418,7 @@ def truncate_tuple(tuple_value: tuple[Any, ...]) -> tuple[Any, ...]:
     assert p.colorimetric_intent is None
     assert p.connection_space == "XYZ "
     assert p.copyright == "Copyright International Color Consortium, 2009"
-    assert p.creation_date == datetime.datetime(2009, 2, 27, 21, 36, 31)
+    assert p.creation_date == datetime.datetime(2009, 3, 27, 21, 36, 31)
     assert p.device_class == "mntr"
     assert_truncated_tuple_equal(
         p.green_colorant,
diff --git a/src/_imagingcms.c b/src/_imagingcms.c
index 6731330de3a..1e588d70d44 100644
--- a/src/_imagingcms.c
+++ b/src/_imagingcms.c
@@ -1034,7 +1034,13 @@ cms_profile_getattr_creation_date(CmsProfileObject *self, void *closure) {
     }
 
     return PyDateTime_FromDateAndTime(
-        1900 + ct.tm_year, ct.tm_mon, ct.tm_mday, ct.tm_hour, ct.tm_min, ct.tm_sec, 0
+        1900 + ct.tm_year,
+        ct.tm_mon + 1,
+        ct.tm_mday,
+        ct.tm_hour,
+        ct.tm_min,
+        ct.tm_sec,
+        0
     );
 }