diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 3b52c3cf2..aea20330f 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -74,7 +74,7 @@ cd sendgrid-php
 composer install
 ```
 
-## Environment Variables
+### Environment Variables
 
 First, get your free SendGrid account [here](https://sendgrid.com/free?source=sendgrid-php).