diff --git a/emails/message.py b/emails/message.py
index eec2a78..cca653f 100644
--- a/emails/message.py
+++ b/emails/message.py
@@ -224,7 +224,8 @@ class MessageBuildMixin(object):
             self.set_header(msg, 'Subject', subject)
 
         self.set_header(msg, 'From', self.encode_address_header(self._mail_from), encode=False)
-        self.set_header(msg, 'To', self._mail_to and self.encode_address_header(self._mail_to[0]) or None, encode=False)
+        self.set_header(msg, 'To', self._mail_to and ", ".join([self.encode_address_header(addr)
+                                                                for addr in self._mail_to]) or None, encode=False)
 
         return msg
 
diff --git a/emails/testsuite/message/test_message.py b/emails/testsuite/message/test_message.py
index e21dce1..3a16434 100644
--- a/emails/testsuite/message/test_message.py
+++ b/emails/testsuite/message/test_message.py
@@ -170,3 +170,13 @@ def test_message_id():
     m = Message(message_id='XXX', **params)
     assert m.as_message()['Message-ID'] == 'XXX'
 
+
+def test_several_recipients_in_to_header():
+    params = dict(html='...', mail_from='a@b.c')
+
+    m = Message(mail_to=['d@e.f', 'g@h.i'], **params)
+    assert m.as_message()['To'] == 'd@e.f, g@h.i'
+
+    m = Message(mail_to=[('♡', 'd@e.f'), ('웃', 'g@h.i')], **params)
+    assert m.as_message()['To'] == '=?utf-8?b?4pmh?= <d@e.f>, =?utf-8?b?7JuD?= <g@h.i>'
+