diff --git a/AUTHORS.txt b/AUTHORS.txt
index bc258d6b..afde43ad 100644
--- a/AUTHORS.txt
+++ b/AUTHORS.txt
@@ -34,5 +34,6 @@ Phillip Berndt (@phillipberndt) <phillip.berndt@gmail.com>
 Ian Lee (@IanLee1521) <IanLee1521@gmail.com>
 Farkhad Khatamov (@hatamov) <comsgn@gmail.com>
 Kevin Kelley (@kelleyk) <kelleyk@kelleyk.net>
+Dmytro Sadovnychyi (@sadovnychyi) <jedi@dmit.ro>
 
 Note: (@user) means a github user name.
diff --git a/jedi/common.py b/jedi/common.py
index 0e9afd11..911227f7 100644
--- a/jedi/common.py
+++ b/jedi/common.py
@@ -134,7 +134,7 @@ def source_to_unicode(source, encoding=None):
             return possible_encoding.group(1)
         else:
             # the default if nothing else has been set -> PEP 263
-            return encoding if encoding is not None else 'iso-8859-1'
+            return encoding if encoding is not None else 'utf-8'
 
     if isinstance(source, unicode):
         # only cast str/bytes