diff --git a/can/io/asc.py b/can/io/asc.py
index 9d854ab0f..c83458ab4 100644
--- a/can/io/asc.py
+++ b/can/io/asc.py
@@ -147,7 +147,7 @@ class ASCWriter(BaseIOHandler, Listener):
             "{bit_timing_conf_ext_data:>8}",
         ]
     )
-    FORMAT_DATE = "%a %b %m %I:%M:%S.{} %p %Y"
+    FORMAT_DATE = "%a %b %d %I:%M:%S.{} %p %Y"
     FORMAT_EVENT = "{timestamp: 9.6f} {message}\n"
 
     def __init__(self, file, channel=1):
@@ -162,7 +162,7 @@ def __init__(self, file, channel=1):
         self.channel = channel
 
         # write start of file header
-        now = datetime.now().strftime("%a %b %m %I:%M:%S.%f %p %Y")
+        now = datetime.now().strftime("%a %b %d %I:%M:%S.%f %p %Y")
         self.file.write("date %s\n" % now)
         self.file.write("base hex  timestamps absolute\n")
         self.file.write("internal events logged\n")