diff --git a/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/billing.json b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/billing.json
index 38e006b05097..680b35022642 100644
--- a/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/billing.json
+++ b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/billing.json
@@ -4473,6 +4473,52 @@
             }
           }
         }
+      },
+      "put": {
+        "tags": [
+          "BillingRoleAssignments"
+        ],
+        "operationId": "RoleAssignments_Put",
+        "description": "Create or update a billing role assignment.",
+        "x-ms-examples": {
+          "PutEnrollmentAdministratorRoleAssignment": {
+            "$ref": "./examples/PutAdministratorRoleAssignment.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "#/parameters/apiVersionParameter"
+          },
+          {
+            "$ref": "#/parameters/billingAccountNameParameter"
+          },
+          {
+            "$ref": "#/parameters/billingRoleAssignmentNameParameter"
+          },
+          {
+            "name": "parameters",
+            "in": "body",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/BillingRoleAssignment"
+            },
+            "description": "The new or updated billing role assignment."
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK. The request has succeeded.",
+            "schema": {
+              "$ref": "#/definitions/BillingRoleAssignment"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed.",
+            "schema": {
+              "$ref": "#/definitions/ErrorResponse"
+            }
+          }
+        }
       }
     },
     "/providers/Microsoft.Billing/billingAccounts/{billingAccountName}/billingProfiles/{billingProfileName}/invoiceSections/{invoiceSectionName}/billingRoleAssignments/{billingRoleAssignmentName}": {
@@ -4725,6 +4771,55 @@
             }
           }
         }
+      },
+      "put": {
+        "tags": [
+          "BillingRoleAssignments"
+        ],
+        "operationId": "EnrollmentDepartmentRoleAssignments_Put",
+        "description": "Create or update a billing role assignment.",
+        "x-ms-examples": {
+          "PutEnrollmentDepartmentAdministratorRoleAssignment": {
+            "$ref": "./examples/PutEnrollmentDepartmentAdministratorRoleAssignment.json"
+          }
+        },
+        "parameters": [
+          {
+            "$ref": "#/parameters/apiVersionParameter"
+          },
+          {
+            "$ref": "#/parameters/billingAccountNameParameter"
+          },
+          {
+            "$ref": "#/parameters/departmentNameParameter"
+          },
+          {
+            "$ref": "#/parameters/billingRoleAssignmentNameParameter"
+          },
+          {
+            "name": "parameters",
+            "in": "body",
+            "required": true,
+            "schema": {
+              "$ref": "#/definitions/BillingRoleAssignment"
+            },
+            "description": "The new or updated billing role assignment."
+          }
+        ],
+        "responses": {
+          "200": {
+            "description": "OK. The request has succeeded.",
+            "schema": {
+              "$ref": "#/definitions/BillingRoleAssignment"
+            }
+          },
+          "default": {
+            "description": "Error response describing why the operation failed.",
+            "schema": {
+              "$ref": "#/definitions/ErrorResponse"
+            }
+          }
+        }
       }
     },
     "/providers/Microsoft.Billing/billingAccounts/{billingAccountName}/enrollmentAccounts/{enrollmentAccountName}/billingRoleAssignments/{billingRoleAssignmentName}": {
diff --git a/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutAdministratorRoleAssignment.json b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutAdministratorRoleAssignment.json
new file mode 100644
index 000000000000..927ad134c30c
--- /dev/null
+++ b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutAdministratorRoleAssignment.json
@@ -0,0 +1,32 @@
+{
+  "parameters": {
+    "api-version": "2019-10-01-preview",
+    "billingAccountName": "{billingAccountName}",
+    "billingRoleAssignmentName": "{billingRoleAssignmentName}",
+    "parameters": {
+      "properties": {
+        "principalId": "99a1a759-30dd-42c2-828c-db398826bb67",
+        "principalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+        "roleDefinitionId": "/providers/Microsoft.Billing/billingAccounts/7898901/billingRoleDefinitions/9f1983cb-2574-400c-87e9-34cf8e2280db"
+      }
+    }
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "id": "/providers/Microsoft.Billing/billingAccounts/7898901/billingRoleAssignments/9dfd08c2-62a3-4d47-85bd-1cdba1408402",
+        "name": "9dfd08c2-62a3-4d47-85bd-1cdba1408402",
+        "properties": {
+          "createdOn": "2019-06-28T19:11:50.6168809+00:00",
+          "createdByPrincipalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+          "createdByPrincipalId": "60d97094-2be4-46cc-a4fe-3633021a25b9",
+          "principalId": "99a1a759-30dd-42c2-828c-db398826bb67",
+          "principalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+          "roleDefinitionId": "/providers/Microsoft.Billing/billingAccounts/7898901/billingRoleDefinitions/9f1983cb-2574-400c-87e9-34cf8e2280db",
+          "scope": "/providers/Microsoft.Billing/billingAccounts/7898901"
+        },
+        "type": "Microsoft.Billing/billingAccounts/billingRoleAssignments"
+      }
+    }
+  }
+}
diff --git a/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutEnrollmentDepartmentAdministratorRoleAssignment.json b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutEnrollmentDepartmentAdministratorRoleAssignment.json
new file mode 100644
index 000000000000..ad30ee9ed1f0
--- /dev/null
+++ b/specification/billing/resource-manager/Microsoft.Billing/preview/2019-10-01-preview/examples/PutEnrollmentDepartmentAdministratorRoleAssignment.json
@@ -0,0 +1,33 @@
+{
+  "parameters": {
+    "api-version": "2019-10-01-preview",
+    "billingAccountName": "{billingAccountName}",
+    "departmentName": "{departmentName}",
+    "billingRoleAssignmentName": "{billingRoleAssignmentName}",
+    "parameters": {
+      "properties": {
+        "principalId": "99a1a759-30dd-42c2-828c-db398826bb67",
+        "principalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+        "roleDefinitionId": "/providers/Microsoft.Billing/billingAccounts/7898901/departments/97603/billingRoleDefinitions/fb2cf67f-be5b-42e7-8025-4683c668f840"
+      }
+    }
+  },
+  "responses": {
+    "200": {
+      "body": {
+        "id": "/providers/Microsoft.Billing/billingAccounts/7898901/departments/97603/billingRoleAssignments/9dfd08c2-62a3-4d47-85bd-1cdba1408402",
+        "name": "9dfd08c2-62a3-4d47-85bd-1cdba1408402",
+        "properties": {
+          "createdOn": "2019-06-28T19:11:50.6168809+00:00",
+          "createdByPrincipalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+          "createdByPrincipalId": "60d97094-2be4-46cc-a4fe-3633021a25b9",
+          "principalId": "99a1a759-30dd-42c2-828c-db398826bb67",
+          "principalTenantId": "7ca289b9-c32d-4f01-8566-7ff93261d76f",
+          "roleDefinitionId": "/providers/Microsoft.Billing/billingAccounts/7898901/departments/97603/billingRoleDefinitions/fb2cf67f-be5b-42e7-8025-4683c668f840",
+          "scope": "/providers/Microsoft.Billing/billingAccounts/7898901/departments/97603"
+        },
+        "type": "Microsoft.Billing/billingAccounts/departments/billingRoleAssignments"
+      }
+    }
+  }
+}