diff --git a/.travis.yml b/.travis.yml
index b2ae5e3c..babfa907 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,7 +8,7 @@ cache:
     - node_modules
 
 addons:
-  firefox: "66.0"
+  firefox: latest
   chrome: stable
 
 jobs:
@@ -22,12 +22,12 @@ jobs:
     - if: type = pull_request
       env: POLYMER=2
       addons:
-        firefox: "66.0"
+        firefox: latest
         chrome: stable
     - if: type = pull_request
       env: POLYMER=3
       addons:
-        firefox: "66.0"
+        firefox: latest
         chrome: stable
     - if: type = cron
       env: TEST_SUITE=unit_tests POLYMER=2