diff --git a/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_Get.json b/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_Get.json
index 3b4bf1bcfece..0181d7b2592e 100644
--- a/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_Get.json
+++ b/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_Get.json
@@ -88,7 +88,8 @@
           },
           "status": {
             "lastOperationError": {}
-          }
+          },
+          "portalFqdn": "fleet1-namespace1-abc123.flt.eastus.azmk8s.io"
         },
         "eTag": "\"EtagValue\"",
         "tags": {
diff --git a/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_ListByFleet.json b/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_ListByFleet.json
index a93c8d070298..68ac65d58951 100644
--- a/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_ListByFleet.json
+++ b/specification/containerservice/Fleet.Management/examples/2025-08-01-preview/FleetManagedNamespaces_ListByFleet.json
@@ -90,7 +90,8 @@
               },
               "status": {
                 "lastOperationError": {}
-              }
+              },
+              "portalFqdn": "fleet1-namespace1-abc123.flt.eastus.azmk8s.io"
             },
             "eTag": "\"EtagValue\"",
             "tags": {
diff --git a/specification/containerservice/Fleet.Management/fleetnamespace.tsp b/specification/containerservice/Fleet.Management/fleetnamespace.tsp
index 0b1a7f546136..cb2546d9a7ba 100644
--- a/specification/containerservice/Fleet.Management/fleetnamespace.tsp
+++ b/specification/containerservice/Fleet.Management/fleetnamespace.tsp
@@ -55,6 +55,10 @@ model FleetManagedNamespaceProperties {
   @visibility(Lifecycle.Read)
   @doc("Status information of the last operation for fleet managed namespace.")
   status?: FleetManagedNamespaceStatus;
+
+  @visibility(Lifecycle.Read)
+  @doc("The Azure Portal FQDN of the Fleet hub.")
+  portalFqdn?: string;
 }
 
 @added(Versions.v2025_08_01_preview)
diff --git a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_Get.json b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_Get.json
index 3b4bf1bcfece..0181d7b2592e 100644
--- a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_Get.json
+++ b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_Get.json
@@ -88,7 +88,8 @@
           },
           "status": {
             "lastOperationError": {}
-          }
+          },
+          "portalFqdn": "fleet1-namespace1-abc123.flt.eastus.azmk8s.io"
         },
         "eTag": "\"EtagValue\"",
         "tags": {
diff --git a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_ListByFleet.json b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_ListByFleet.json
index a93c8d070298..68ac65d58951 100644
--- a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_ListByFleet.json
+++ b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/examples/FleetManagedNamespaces_ListByFleet.json
@@ -90,7 +90,8 @@
               },
               "status": {
                 "lastOperationError": {}
-              }
+              },
+              "portalFqdn": "fleet1-namespace1-abc123.flt.eastus.azmk8s.io"
             },
             "eTag": "\"EtagValue\"",
             "tags": {
diff --git a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/fleets.json b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/fleets.json
index 7c98f4fbc7e3..d2e29a035452 100644
--- a/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/fleets.json
+++ b/specification/containerservice/resource-manager/Microsoft.ContainerService/fleet/preview/2025-08-01-preview/fleets.json
@@ -3430,6 +3430,11 @@
           "$ref": "#/definitions/FleetManagedNamespaceStatus",
           "description": "Status information of the last operation for fleet managed namespace.",
           "readOnly": true
+        },
+        "portalFqdn": {
+          "type": "string",
+          "description": "The Azure Portal FQDN of the Fleet hub.",
+          "readOnly": true
         }
       },
       "required": [