diff --git a/homeassistant/const.py b/homeassistant/const.py
index bbd9de7585b..d9396188487 100644
--- a/homeassistant/const.py
+++ b/homeassistant/const.py
@@ -1,7 +1,7 @@
 # coding: utf-8
 """Constants used by Home Assistant components."""
 
-__version__ = "0.19"
+__version__ = "0.20.0.dev0"
 REQUIRED_PYTHON_VER = (3, 4)
 
 PLATFORM_FORMAT = '{}.{}'