diff --git a/mailchimp3/helpers.py b/mailchimp3/helpers.py
index <HASH>..<HASH> 100644
--- a/mailchimp3/helpers.py
+++ b/mailchimp3/helpers.py
@@ -52,13 +52,14 @@ def check_email(email):
     """
     Function that verifies that the string passed is a valid email address.
 
-    Regex for email validation from http://emailregex.com/
+    Regex for email validation based on MailChimp limits:
+    http://kb.mailchimp.com/accounts/management/international-characters-in-mailchimp
 
     :param email: The potential email address
     :type email: :py:class:`str`
     :return: Nothing
     """
-    if '@' not in email:
+    if not re.match(r"[a-zA-Z0-9_+-.]+@.+\.[^.]+", email):
         raise ValueError('String passed is not a valid email address')
     return
Switch back to regex matching Mailchimp's documentation, and update docstring.