diff --git a/.travis.yml b/.travis.yml
index e20d06c4..641e852d 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -31,7 +31,7 @@ cache:
 #   - sudo chmod +x /usr/local/bin/sbt
 
 after_success:
-  - '[[ $TRAVIS_BRANCH == "master" ]] && [[ $TRAVIS_JDK_VERSION == "openjdk11" ]] && { sbt  ++$TRAVIS_SCALA_VERSION publish; };'
+  - '[[ $TRAVIS_BRANCH == "master" ]] && [[ $TRAVIS_JDK_VERSION == "openjdk11" ]] && [[ $SONATYPE_USERNAME != "" ]] && { sbt  ++$TRAVIS_SCALA_VERSION publish; };'
 
 env:
   global: