diff --git a/.travis.yml b/.travis.yml
index b2499b5..60731be 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -14,11 +14,11 @@
   include:
   - language: generic
     os: osx
-    osx_image: xcode8.3
+    osx_image: xcode9.3
     env: TOXENV=py27
   - language: generic
     os: osx
-    osx_image: xcode8.3
+    osx_image: xcode9.3
     env: TOXENV=py27 OPENSSL=1.1.0
   - python: "2.7" # these are just to make travis's UI a bit prettier
     env: TOXENV=py27