diff --git a/.travis.yml b/.travis.yml
index 22f6ed7b..eed0f8e5 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -9,12 +9,12 @@ matrix:
   include:
     - os: osx
       osx_image: xcode7.3	# OS X 10.11
-    - os: osx
-      osx_image: xcode8     # OS X 10.11
-    - os: osx
-      osx_image: xcode8.1   # OS X 10.12
     - os: osx
       osx_image: xcode8.3   # OS X 10.12
+    - os: osx
+      osx_image: xcode9     # OS X 10.13
+    - os: osx
+      osx_image: xcode9.1   # OS X 10.13.1
     - os: linux
       dist: trusty
       sudo: required