diff --git a/CHANGELOG.md b/CHANGELOG.md
index df6df3eb2..843cd9cce 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -111,7 +111,7 @@ Thankyou! -->
     1. Add `host` profile to base_event.json and remove this profile elsewhere in the event hierarchy. #1280
     1. Add the `actor` attribute to the IAM base event. #1280
     1. Add `security_control` profile to base_event.json and remove this profile elsewhere in the event hierarchy. #1281
-
+    1. Add `Unlock` activity to `account_change` class. #1285
 * #### Profiles
     1. Added `is_alert`, `confidence_id`, `confidence`, `confidence_score` attributes to the `security_control` profile. #1178
     1. Added `risk_level_id`, `risk_level`, `risk_score`, `risk_details` attributes to the `security_control` profile.  #1178
diff --git a/events/iam/account_change.json b/events/iam/account_change.json
index bf35fa187..59efcb66c 100644
--- a/events/iam/account_change.json
+++ b/events/iam/account_change.json
@@ -50,6 +50,10 @@
         "11": {
           "caption": "MFA Factor Disable",
           "description": "An authentication factor was disabled for an account."
+        },
+        "12": {
+          "caption": "Unlock",
+          "description": "A user account was unlocked."
         }
       }
     },
@@ -69,4 +73,4 @@
       "requirement": "recommended"
     }
   }
-}
\ No newline at end of file
+}