diff --git a/README.md b/README.md
index d5de68b..3d40a75 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,9 @@
 The paid-signs plugin is a plugin that lets you add costs for creating plugin signs. This allows restricting usage of
 signs such as CraftBook's gate/lift and other signs while still allowing every player to use the signs.
 
+Note: OP players, and players with the '*' permission will have the `paidsigns.paymentexempt` permission and will not
+see any payment messages. For testing, you'll need to un-set the `paidsigns.paymentexempt` permission.
+
 ## Limitations
 
 As this plugin only listens to sign change events, there are some limitations: