diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 26f814c4..ded03ae3 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -103,6 +103,8 @@ Please don't introduce new spotbugs output.
 Source code and pom file formatting is maintained by the `spotless` maven plugin.
 Before submitting a pull request, confirm the formatting is correct with:
 
+* `mvn spotless:apply`
+
 ## Code coverage
 
 Code coverage reporting is available as a maven target.