diff --git a/CHANGES.md b/CHANGES.md
index c3e94634..f2aac633 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,5 +1,11 @@
 # Change Log
 
+## v.21.0 - 
+
+##### Fixes :wrench:
+
+- Setting CesiumGeoreference.ellipsoid at runtime will now correctly update the Georeference and associated transforms.
+
 ## v1.20.0 - 2025-12-01
 
 ##### Additions :tada:
diff --git a/Runtime/CesiumGeoreference.cs b/Runtime/CesiumGeoreference.cs
index dc7e898d..6f9c0702 100644
--- a/Runtime/CesiumGeoreference.cs
+++ b/Runtime/CesiumGeoreference.cs
@@ -355,7 +355,14 @@ public CesiumEllipsoid ellipsoid
             }
             set
             {
-                this._ellipsoid = value;
+                // Don't set the _ellipsoid field directly; instead, set the ellipsoidOverride,
+                // so that transforms are updated properly. _ellipsoid will be set through that
+                // process.
+                if (this._ellipsoidOverride != value)
+                {
+                    this._ellipsoidOverride = value;
+                    this.ReloadEllipsoid();
+                }
             }
         }