diff --git a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/FrontDoor.tsp b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/FrontDoor.tsp
index b9bf146f7507..e577bb7f384e 100644
--- a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/FrontDoor.tsp
+++ b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/FrontDoor.tsp
@@ -84,6 +84,19 @@ interface FrontDoors {
     Error = ErrorResponse
   >;
 
+  /**
+   * Updates tags of an existing Front Door with the specified Front Door name under the specified subscription and resource group.
+   */
+  #suppress "@azure-tools/typespec-azure-resource-manager/lro-location-header" "Existing service uses Azure-AsyncOperation header only"
+  @patch(#{ implicitOptionality: false })
+  update is ArmCustomPatchAsync<
+    FrontDoor,
+    PatchModel = TagsObject,
+    LroHeaders = ArmAsyncOperationHeader<FinalResult = FrontDoor> &
+      Azure.Core.Foundations.RetryAfterHeader,
+    Error = ErrorResponse
+  >;
+
   /**
    * Validates the custom domain mapping to ensure it maps to the correct Front Door endpoint in DNS.
    */
@@ -122,3 +135,6 @@ interface FrontDoors {
 @@doc(FrontDoors.purgeContent::parameters.body,
   "The path to the content to be purged. Path can be a full URL, e.g. '/pictures/city.png' which removes a single file, or a directory with a wildcard, e.g. '/pictures/*' which removes all folders and files in the directory."
 );
+@@doc(FrontDoors.update::parameters.properties,
+  "Front Door tags to be updated."
+);
diff --git a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-10-01/openapi.json b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-10-01/openapi.json
index 468b400c011c..28216692c634 100644
--- a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-10-01/openapi.json
+++ b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-10-01/openapi.json
@@ -1810,6 +1810,76 @@
         },
         "x-ms-long-running-operation": true
       },
+      "patch": {
+        "operationId": "FrontDoors_Update",
+        "tags": [
+          "FrontDoors"
+        ],
+        "description": "Updates tags of an existing Front Door with the specified Front Door name under the specified subscription and resource group.",
+        "parameters": [
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          },
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/ResourceGroupNameParameter"
+          },
+          {
+            "name": "frontDoorName",
+            "in": "path",
+            "description": "Name of the Front Door which is globally unique.",
+            "required": true,
+            "type": "string",
+            "minLength": 5,
+            "maxLength": 64,
+            "pattern": "^[a-zA-Z0-9]+([-a-zA-Z0-9]?[a-zA-Z0-9])*$"
+          },
+          {
+            "name": "properties",
+            "in": "body",
+            "description": "Front Door tags to be updated.",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/TagsObject"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "#/definitions/FrontDoor"
+            }
+          },
+          "202": {
+            "description": "Resource update request accepted.",
+            "headers": {
+              "Azure-AsyncOperation": {
+                "type": "string",
+                "description": "A link to the status monitor"
+              },
+              "Retry-After": {
+                "type": "integer",
+                "format": "int32",
+                "description": "The Retry-After header can indicate how long the client should wait before polling the operation status."
+              }
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-long-running-operation-options": {
+          "final-state-via": "azure-async-operation",
+          "final-state-schema": "#/definitions/FrontDoor"
+        },
+        "x-ms-long-running-operation": true
+      },
       "delete": {
         "operationId": "FrontDoors_Delete",
         "tags": [
diff --git a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-11-01/openapi.json b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-11-01/openapi.json
index 0f1617818ed8..36350755d977 100644
--- a/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-11-01/openapi.json
+++ b/specification/frontdoor/resource-manager/Microsoft.Network/FrontDoor/stable/2025-11-01/openapi.json
@@ -1810,6 +1810,76 @@
         },
         "x-ms-long-running-operation": true
       },
+      "patch": {
+        "operationId": "FrontDoors_Update",
+        "tags": [
+          "FrontDoors"
+        ],
+        "description": "Updates tags of an existing Front Door with the specified Front Door name under the specified subscription and resource group.",
+        "parameters": [
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/ApiVersionParameter"
+          },
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/SubscriptionIdParameter"
+          },
+          {
+            "$ref": "../../../../../../common-types/resource-management/v3/types.json#/parameters/ResourceGroupNameParameter"
+          },
+          {
+            "name": "frontDoorName",
+            "in": "path",
+            "description": "Name of the Front Door which is globally unique.",
+            "required": true,
+            "type": "string",
+            "minLength": 5,
+            "maxLength": 64,
+            "pattern": "^[a-zA-Z0-9]+([-a-zA-Z0-9]?[a-zA-Z0-9])*$"
+          },
+          {
+            "name": "properties",
+            "in": "body",
+            "description": "Front Door tags to be updated.",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/TagsObject"
+            }
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "Azure operation completed successfully.",
+            "schema": {
+              "$ref": "#/definitions/FrontDoor"
+            }
+          },
+          "202": {
+            "description": "Resource update request accepted.",
+            "headers": {
+              "Azure-AsyncOperation": {
+                "type": "string",
+                "description": "A link to the status monitor"
+              },
+              "Retry-After": {
+                "type": "integer",
+                "format": "int32",
+                "description": "The Retry-After header can indicate how long the client should wait before polling the operation status."
+              }
+            }
+          },
+          "default": {
+            "description": "An unexpected error response.",
+            "schema": {
+              "$ref": "#/definitions/ErrorResponse"
+            }
+          }
+        },
+        "x-ms-long-running-operation-options": {
+          "final-state-via": "azure-async-operation",
+          "final-state-schema": "#/definitions/FrontDoor"
+        },
+        "x-ms-long-running-operation": true
+      },
       "delete": {
         "operationId": "FrontDoors_Delete",
         "tags": [