diff --git a/.travis.yml b/.travis.yml
index 9e1bb55df2..f24986b3d0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -62,4 +62,4 @@ after_success:
       fi
 
 after_script:
-  - "curl -X POST -H 'Content-Type:application/json' -d '{\"attachments\": [{\"color\": \"warning\", \"fallback\": \"Build Notification: $TRAVIS_BUILD_WEB_URL\", \"title\": \"Build Notification\", \"text\": \"$TRAVIS_BUILD_WEB_URL\"}]}' $SLACK_URL"
+  - "curl -X POST -H 'Content-Type:application/json' -d '{\"attachments\": [{\"color\": \"warning\", \"fallback\": \"Build Notification: ${TRAVIS_BUILD_WEB_URL}\", \"title\": \"Build Notification\", \"text\": \"${TRAVIS_BUILD_WEB_URL}\"}]}' $SLACK_URL"