diff --git a/README.md b/README.md
index e86f3a4..aa5d99f 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ Add php-http-client to your `composer.json` file. If you are not using [Composer
 ```json
 {
   "require": {
-    "sendgrid/php-http-client": "^3.14.4"
+    "sendgrid/php-http-client": "^4.0.0"
   }
 }
 ```