diff --git a/customtkinter/windows/widgets/ctk_entry.py b/customtkinter/windows/widgets/ctk_entry.py
index db54386..3a3ec0d 100644
--- a/customtkinter/windows/widgets/ctk_entry.py
+++ b/customtkinter/windows/widgets/ctk_entry.py
@@ -19,7 +19,7 @@ class CTkEntry(CTkBaseClass):
 
     # attributes that are passed to and managed by the tkinter entry only:
     _valid_tk_entry_attributes = {"exportselection", "insertborderwidth", "insertofftime",
-                                  "insertontime", "insertwidth", "justify", "selectborderwidth",
+                                  "insertontime", "insertwidth", "invalidcommand", "justify", "selectborderwidth",
                                   "show", "takefocus", "validate", "validatecommand", "xscrollcommand"}
 
     def __init__(self,