diff --git a/.travis.yml b/.travis.yml
index a1cc380..5215896 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -18,7 +18,10 @@ before_script:
 script:
   - cargo build --all --locked --verbose
   - cargo test --all --locked --verbose
-  - cargo fmt --all -- --check
+  - |
+    if [[ "$TRAVIS_RUST_VERSION" == "stable" ]]; then
+      cargo fmt --all -- --check
+    fi
 
 jobs:
   allow_failures:
diff --git a/appveyor.yml b/appveyor.yml
index adf84e2..d15c249 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -128,4 +128,3 @@ build: false
 # environment variable.
 test_script:
   - cargo test --verbose %cargoflags%
-  - cargo fmt --all -- --check