diff --git a/tools/ci/travis-install.sh b/tools/ci/travis-install.sh
index cc707d861b..670f28f33b 100755
--- a/tools/ci/travis-install.sh
+++ b/tools/ci/travis-install.sh
@@ -23,12 +23,12 @@ fi
 # Build and install OpenMC executable
 python tools/ci/travis-install.py
 
-# Install Python API in editable mode
-pip install -e .[test]
-
-# conditionally install vtk
-if [ $TRAVIS_PYTHON_VERSION -ne 3.7 ]; then
-    pip install -e .[vtk]
+if [[ $TRAVIS_PYTHON_VERSION == "3.7" ]]; then
+    # Install Python API in editable mode
+    pip install -e .[test]
+else
+    # Conditionally install vtk
+    pip install -e .[test,vtk]
 fi
 
 # For uploading to coveralls