diff --git a/modules/openapi-generator/src/main/resources/dart/libraries/dio/api.mustache b/modules/openapi-generator/src/main/resources/dart/libraries/dio/api.mustache
index 86a3a87162a..80b935c2421 100644
--- a/modules/openapi-generator/src/main/resources/dart/libraries/dio/api.mustache
+++ b/modules/openapi-generator/src/main/resources/dart/libraries/dio/api.mustache
@@ -39,11 +39,11 @@ class {{classname}} {
   @Deprecated('This operation has been deprecated')
   {{/isDeprecated}}
   Future<Response<{{{returnType}}}{{^returnType}}void{{/returnType}}>> {{nickname}}({ {{#allParams}}{{#isPathParam}}
-    required {{{dataType}}} {{paramName}},{{/isPathParam}}{{#isQueryParam}}
-    {{#required}}{{^isNullable}}{{^defaultValue}}required {{/defaultValue}}{{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}}{{^isContainer}}{{#defaultValue}} = {{{.}}}{{/defaultValue}}{{/isContainer}},{{/isQueryParam}}{{#isHeaderParam}}
-    {{#required}}{{^isNullable}}{{^defaultValue}}required {{/defaultValue}}{{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}}{{^isContainer}}{{#defaultValue}} = {{{.}}}{{/defaultValue}}{{/isContainer}},{{/isHeaderParam}}{{#isBodyParam}}
-    {{#required}}{{^isNullable}}required {{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}},{{/isBodyParam}}{{#isFormParam}}
-    {{#required}}{{^isNullable}}required {{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}},{{/isFormParam}}{{/allParams}}
+    {{#isDeprecated}}@Deprecated('{{paramName}} is deprecated') {{/isDeprecated}}required {{{dataType}}} {{paramName}},{{/isPathParam}}{{#isQueryParam}}
+    {{#isDeprecated}}@Deprecated('{{paramName}} is deprecated') {{/isDeprecated}}{{#required}}{{^isNullable}}{{^defaultValue}}required {{/defaultValue}}{{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}}{{^isContainer}}{{#defaultValue}} = {{{.}}}{{/defaultValue}}{{/isContainer}},{{/isQueryParam}}{{#isHeaderParam}}
+    {{#isDeprecated}}@Deprecated('{{paramName}} is deprecated') {{/isDeprecated}}{{#required}}{{^isNullable}}{{^defaultValue}}required {{/defaultValue}}{{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}}{{^isContainer}}{{#defaultValue}} = {{{.}}}{{/defaultValue}}{{/isContainer}},{{/isHeaderParam}}{{#isBodyParam}}
+    {{#isDeprecated}}@Deprecated('{{paramName}} is deprecated') {{/isDeprecated}}{{#required}}{{^isNullable}}required {{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}},{{/isBodyParam}}{{#isFormParam}}
+    {{#isDeprecated}}@Deprecated('{{paramName}} is deprecated') {{/isDeprecated}}{{#required}}{{^isNullable}}required {{/isNullable}}{{/required}}{{{dataType}}}{{#required}}{{#isNullable}}?{{/isNullable}}{{/required}}{{^required}}?{{/required}} {{paramName}},{{/isFormParam}}{{/allParams}}
     CancelToken? cancelToken,
     Map<String, dynamic>? headers,
     Map<String, dynamic>? extra,
diff --git a/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/built_value/class_members.mustache b/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/built_value/class_members.mustache
index 45c68d0980f..0df06e1e307 100644
--- a/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/built_value/class_members.mustache
+++ b/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/built_value/class_members.mustache
@@ -3,9 +3,9 @@
   {{#description}}
   /// {{{.}}}
   {{/description}}
-  {{#isDeprecated}}
+  {{#deprecated}}
   @Deprecated('{{{name}}} has been deprecated')
-  {{/isDeprecated}}
+  {{/deprecated}}
   @BuiltValueField(wireName: r'{{baseName}}')
   {{>serialization/built_value/variable_type}}{{^isNullable}}{{^required}}?{{/required}}{{/isNullable}} get {{name}};
   {{#allowableValues}}
diff --git a/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/json_serializable/class.mustache b/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/json_serializable/class.mustache
index b4c10ab8e1c..4bc0161261e 100644
--- a/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/json_serializable/class.mustache
+++ b/modules/openapi-generator/src/main/resources/dart/libraries/dio/serialization/json_serializable/class.mustache
@@ -35,9 +35,9 @@ class {{{classname}}} {
           // maximum: {{{maximum}}}
       {{/maximum}}
   {{/isEnum}}
-  {{#isDeprecated}}
+  {{#deprecated}}
   @Deprecated('{{{name}}} has been deprecated')
-  {{/isDeprecated}}
+  {{/deprecated}}
   {{^isBinary}}
   @JsonKey(
     {{#defaultValue}}defaultValue: {{{defaultValue}}},{{/defaultValue}}
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/api/pet_api.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/api/pet_api.dart
index e7abc3a8970..fa86eaac1d8 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/api/pet_api.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/api/pet_api.dart
@@ -158,7 +158,7 @@ _bodyData=jsonEncode(pet);
   /// Returns a [Future] containing a [Response] with a [List<Pet>] as data
   /// Throws [DioError] if API call or serialization fails
   Future<Response<List<Pet>>> findPetsByStatus({ 
-    required List<String> status,
+    @Deprecated('status is deprecated') required List<String> status,
     CancelToken? cancelToken,
     Map<String, dynamic>? headers,
     Map<String, dynamic>? extra,
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/deprecated_object.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/deprecated_object.dart
index e4371fdc696..0151b72e23a 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/deprecated_object.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/deprecated_object.dart
@@ -22,7 +22,6 @@ class DeprecatedObject {
      this.name,
   });
 
-  @Deprecated('name has been deprecated')
   @JsonKey(
     
     name: r'name',
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/object_with_deprecated_fields.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/object_with_deprecated_fields.dart
index 17361613609..e4eb5263113 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/object_with_deprecated_fields.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake-json_serializable/lib/src/model/object_with_deprecated_fields.dart
@@ -40,6 +40,7 @@ class ObjectWithDeprecatedFields {
 
 
 
+  @Deprecated('id has been deprecated')
   @JsonKey(
     
     name: r'id',
@@ -52,6 +53,7 @@ class ObjectWithDeprecatedFields {
 
 
 
+  @Deprecated('deprecatedRef has been deprecated')
   @JsonKey(
     
     name: r'deprecatedRef',
@@ -64,6 +66,7 @@ class ObjectWithDeprecatedFields {
 
 
 
+  @Deprecated('bars has been deprecated')
   @JsonKey(
     
     name: r'bars',
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/api/pet_api.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/api/pet_api.dart
index 772f60146e4..2ff77083680 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/api/pet_api.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/api/pet_api.dart
@@ -162,7 +162,7 @@ class PetApi {
   /// Returns a [Future] containing a [Response] with a [BuiltList<Pet>] as data
   /// Throws [DioError] if API call or serialization fails
   Future<Response<BuiltList<Pet>>> findPetsByStatus({ 
-    required BuiltList<String> status,
+    @Deprecated('status is deprecated') required BuiltList<String> status,
     CancelToken? cancelToken,
     Map<String, dynamic>? headers,
     Map<String, dynamic>? extra,
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/deprecated_object.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/deprecated_object.dart
index 6ed0ecf6b09..57f089c899c 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/deprecated_object.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/deprecated_object.dart
@@ -15,7 +15,6 @@ part 'deprecated_object.g.dart';
 @Deprecated('DeprecatedObject has been deprecated')
 @BuiltValue()
 abstract class DeprecatedObject implements Built<DeprecatedObject, DeprecatedObjectBuilder> {
-  @Deprecated('name has been deprecated')
   @BuiltValueField(wireName: r'name')
   String? get name;
 
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/object_with_deprecated_fields.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/object_with_deprecated_fields.dart
index f59131ea6fb..4e0ae04ae50 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/object_with_deprecated_fields.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake/lib/src/model/object_with_deprecated_fields.dart
@@ -22,12 +22,15 @@ abstract class ObjectWithDeprecatedFields implements Built<ObjectWithDeprecatedF
   @BuiltValueField(wireName: r'uuid')
   String? get uuid;
 
+  @Deprecated('id has been deprecated')
   @BuiltValueField(wireName: r'id')
   num? get id;
 
+  @Deprecated('deprecatedRef has been deprecated')
   @BuiltValueField(wireName: r'deprecatedRef')
   DeprecatedObject? get deprecatedRef;
 
+  @Deprecated('bars has been deprecated')
   @BuiltValueField(wireName: r'bars')
   BuiltList<String>? get bars;
 
diff --git a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests/test/api/pet_api_test.dart b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests/test/api/pet_api_test.dart
index 6e32e3cd97e..af0363a2eda 100644
--- a/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests/test/api/pet_api_test.dart
+++ b/samples/openapi3/client/petstore/dart-dio/petstore_client_lib_fake_tests/test/api/pet_api_test.dart
@@ -198,6 +198,7 @@ void main() {
         );
 
         final response = await client.getPetApi().findPetsByStatus(
+              // ignore: deprecated_member_use
               status: ListBuilder<String>(<String>[
                 PetStatusEnum.available.name,
                 PetStatusEnum.sold.name,