diff --git a/micromail.py b/micromail.py
index 966d0f6..f3be346 100644
--- a/micromail.py
+++ b/micromail.py
@@ -176,7 +176,7 @@ class MicromailClient:
 
         self.send_command("DATA", code=354)
 
-    def headers(self, headers: dict[str, str]) -> None:
+    def headers(self, headers: dict[str, str] = {}) -> None:
         date = headers.get("date", format_date(datetime.now(tz=timezone(timedelta()))))
         self.write(f"Date: {date}\r\n")