diff --git a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt
index ac1ff11dfe10..9ecdf8b7c7d0 100644
--- a/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt
+++ b/packages/react-native/ReactAndroid/src/main/java/com/facebook/react/internal/featureflags/ReactNativeFeatureFlagsDefaults.kt
@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<fcee66a9800d5b3b1105df73d33feea9>>
+ * @generated SignedSource<<07ea15d4fd3f3bc73c8f49cd24724caf>>
  */
 
 /**
@@ -71,7 +71,7 @@ public open class ReactNativeFeatureFlagsDefaults : ReactNativeFeatureFlagsProvi
 
   override fun enableMainQueueModulesOnIOS(): Boolean = false
 
-  override fun enableModuleArgumentNSNullConversionIOS(): Boolean = true
+  override fun enableModuleArgumentNSNullConversionIOS(): Boolean = false
 
   override fun enableNativeCSSParsing(): Boolean = false
 
diff --git a/packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsDefaults.h b/packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsDefaults.h
index 9b6fcd9ffeda..58a4520dab37 100644
--- a/packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsDefaults.h
+++ b/packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlagsDefaults.h
@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<c80be05a320b2cb0e78865492f503922>>
+ * @generated SignedSource<<6692978a1497fa9e99d539511388c9fa>>
  */
 
 /**
@@ -124,7 +124,7 @@ class ReactNativeFeatureFlagsDefaults : public ReactNativeFeatureFlagsProvider {
   }
 
   bool enableModuleArgumentNSNullConversionIOS() override {
-    return true;
+    return false;
   }
 
   bool enableNativeCSSParsing() override {
diff --git a/packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js b/packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js
index 00eeb4034dcf..9e7249b0b9e0 100644
--- a/packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js
+++ b/packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js
@@ -300,7 +300,7 @@ const definitions: FeatureFlagDefinitions = {
       ossReleaseStage: 'none',
     },
     enableModuleArgumentNSNullConversionIOS: {
-      defaultValue: true,
+      defaultValue: false,
       metadata: {
         description:
           'Enable NSNull conversion when handling module arguments on iOS',
diff --git a/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js b/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
index d4ade2d60805..8096ad8c0565 100644
--- a/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
+++ b/packages/react-native/src/private/featureflags/ReactNativeFeatureFlags.js
@@ -4,7 +4,7 @@
  * This source code is licensed under the MIT license found in the
  * LICENSE file in the root directory of this source tree.
  *
- * @generated SignedSource<<cbcc6da9a0d0652dddd99977690a258a>>
+ * @generated SignedSource<<4d96a5f9132ea827faeb183fe8bbf095>>
  * @flow strict
  * @noformat
  */
@@ -281,7 +281,7 @@ export const enableMainQueueModulesOnIOS: Getter<boolean> = createNativeFlagGett
 /**
  * Enable NSNull conversion when handling module arguments on iOS
  */
-export const enableModuleArgumentNSNullConversionIOS: Getter<boolean> = createNativeFlagGetter('enableModuleArgumentNSNullConversionIOS', true);
+export const enableModuleArgumentNSNullConversionIOS: Getter<boolean> = createNativeFlagGetter('enableModuleArgumentNSNullConversionIOS', false);
 /**
  * Parse CSS strings using the Fabric CSS parser instead of ViewConfig processing
  */