diff --git a/composer.json b/composer.json
index c562752b0..f72cfc0a5 100644
--- a/composer.json
+++ b/composer.json
@@ -15,7 +15,7 @@
     },
     "require-dev": {
         "woocommerce/woocommerce-sniffs": "^0.1.0",
-        "phpunit/phpunit": "^9.1",
+        "phpunit/phpunit": "^7.0 | ^8.0 | ^9.0",
         "brain/monkey": "^2.4"
     },
     "autoload": {