diff --git a/README.rst b/README.rst
index 8e5c5fb..d70095b 100644
--- a/README.rst
+++ b/README.rst
@@ -15,7 +15,7 @@ even outside of the admin.
    :alt: Build Status - master branch
    :target: https://travis-ci.org/kunitoki/django-custard
 
-.. |coveralls| image:: https://coveralls.io/repos/kunitoki/django-custard/badge.png
+.. |coveralls| image:: https://coveralls.io/repos/kunitoki/django-custard/badge.png?branch=master
    :alt: Source code coverage - master branch
    :target: https://coveralls.io/r/kunitoki/django-custard
 
diff --git a/docs/index.rst b/docs/index.rst
index 86f354b..2eb1eab 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -15,7 +15,7 @@ even outside of the admin.
    :alt: Build Status - master branch
    :target: https://travis-ci.org/kunitoki/django-custard
 
-.. |coveralls| image:: https://coveralls.io/repos/kunitoki/django-custard/badge.png
+.. |coveralls| image:: https://coveralls.io/repos/kunitoki/django-custard/badge.png?branch=master
    :alt: Source code coverage - master branch
    :target: https://coveralls.io/r/kunitoki/django-custard