diff --git a/Projects/UOContent.Tests/Tests/Mobiles/AI/AIDeactivationTests.cs b/Projects/UOContent.Tests/Tests/Mobiles/AI/AIDeactivationTests.cs
new file mode 100644
index 000000000..fc3f82aa8
--- /dev/null
+++ b/Projects/UOContent.Tests/Tests/Mobiles/AI/AIDeactivationTests.cs
@@ -0,0 +1,33 @@
+using Server;
+using Xunit;
+
+namespace UOContent.Tests.Mobiles.AI;
+
+[Collection("Sequential UOContent Tests")]
+public class AIDeactivationTests
+{
+    [Theory]
+    [InlineData(false, false)]
+    [InlineData(false, true)]
+    [InlineData(true, false)]
+    [InlineData(true, true)]
+    public void Deactivate_WithoutWorldMap_StopsTimer(bool internalMap, bool controlled)
+    {
+        var creature = new PetTestStub();
+        try
+        {
+            creature.Controlled = controlled;
+            creature.Map = internalMap ? Map.Internal : null;
+            creature.AIObject.Activate();
+            Assert.True(creature.AIObject.AITimer.Running);
+
+            creature.AIObject.Deactivate();
+
+            Assert.False(creature.AIObject.AITimer.Running);
+        }
+        finally
+        {
+            creature.Delete();
+        }
+    }
+}
diff --git a/Projects/UOContent/Mobiles/AI/BaseAI/BaseAI.cs b/Projects/UOContent/Mobiles/AI/BaseAI/BaseAI.cs
index e7b16be9c..e762c5c61 100644
--- a/Projects/UOContent/Mobiles/AI/BaseAI/BaseAI.cs
+++ b/Projects/UOContent/Mobiles/AI/BaseAI/BaseAI.cs
@@ -1102,7 +1102,7 @@ public abstract partial class BaseAI
 
     public virtual void Deactivate()
     {
-        if (Mobile.Map == Map.Internal || !Mobile.Controlled && !Mobile.Map.GetSector(Mobile.Location).Active)
+        if (Mobile.Map == null || Mobile.Map == Map.Internal || !Mobile.Controlled && !Mobile.Map.GetSector(Mobile.Location).Active)
         {
             AITimer.Stop();
         }