diff --git a/app/api/views/mailbox.py b/app/api/views/mailbox.py
index 4d112790..517148ac 100644
--- a/app/api/views/mailbox.py
+++ b/app/api/views/mailbox.py
@@ -30,7 +30,7 @@ def create_mailbox():
 
     """
     user = g.user
-    mailbox_email = request.get_json().get("email").lower().strip()
+    mailbox_email = request.get_json().get("email").lower().strip().replace(" ", "")
 
     if mailbox_already_used(mailbox_email, user):
         return jsonify(error=f"{mailbox_email} already used"), 400
diff --git a/app/dashboard/views/mailbox.py b/app/dashboard/views/mailbox.py
index 6b0da7e3..a14333fa 100644
--- a/app/dashboard/views/mailbox.py
+++ b/app/dashboard/views/mailbox.py
@@ -82,7 +82,9 @@ def mailbox_route():
                 return redirect(url_for("dashboard.mailbox_route"))
 
             if new_mailbox_form.validate():
-                mailbox_email = new_mailbox_form.email.data.lower().strip()
+                mailbox_email = (
+                    new_mailbox_form.email.data.lower().strip().replace(" ", "")
+                )
 
                 if mailbox_already_used(mailbox_email, current_user):
                     flash(f"{mailbox_email} already used", "error")