diff --git a/cockatrice/src/tab_supervisor.cpp b/cockatrice/src/tab_supervisor.cpp
index 166a766ab..48e7cc238 100644
--- a/cockatrice/src/tab_supervisor.cpp
+++ b/cockatrice/src/tab_supervisor.cpp
@@ -446,11 +446,27 @@ void TabSupervisor::processGameEventContainer(const GameEventContainer &cont)
 
 void TabSupervisor::processUserMessageEvent(const Event_UserMessage &event)
 {
-    TabMessage *tab = messageTabs.value(QString::fromStdString(event.sender_name()));
+    QString senderName = QString::fromStdString(event.sender_name());
+
+    UserListTWI *twi = tabUserLists->getAllUsersList()->getUsers().value(senderName);
+
+    ServerInfo_User otherUser;
+
+    if (twi)
+        otherUser = twi->getUserInfo();
+    else
+        otherUser.set_name(senderName.toStdString());
+
+    UserLevelFlags otherUserLevel = UserLevelFlags(otherUser.user_level());
+
+    if (settingsCache->getIgnoreUnregisteredUsers() && !otherUserLevel.testFlag(ServerInfo_User::IsRegistered))
+        return;
+
+    TabMessage *tab = messageTabs.value(senderName);
     if (!tab)
         tab = messageTabs.value(QString::fromStdString(event.receiver_name()));
     if (!tab)
-        tab = addMessageTab(QString::fromStdString(event.sender_name()), false);
+        tab = addMessageTab(senderName, false);
     if (!tab)
         return;
     tab->processUserMessageEvent(event);