diff --git a/packages/react-native/Libraries/Animated/animations/Animation.js b/packages/react-native/Libraries/Animated/animations/Animation.js
index b071a89661b1f1..238958f14900ed 100644
--- a/packages/react-native/Libraries/Animated/animations/Animation.js
+++ b/packages/react-native/Libraries/Animated/animations/Animation.js
@@ -168,7 +168,7 @@ export default class Animation {
       );
 
       return true;
-    } catch (e) {
+    } catch (e: unknown) {
       throw e;
     } finally {
       NativeAnimatedHelper.API.unsetWaitingForIdentifier(
diff --git a/packages/react-native/Libraries/BatchedBridge/MessageQueue.js b/packages/react-native/Libraries/BatchedBridge/MessageQueue.js
index fe557ed59c1485..4f18c0686c28f2 100644
--- a/packages/react-native/Libraries/BatchedBridge/MessageQueue.js
+++ b/packages/react-native/Libraries/BatchedBridge/MessageQueue.js
@@ -372,7 +372,7 @@ class MessageQueue {
     } else {
       try {
         fn();
-      } catch (error) {
+      } catch (error: unknown) {
         ErrorUtils.reportFatalError(error);
       }
     }
diff --git a/packages/react-native/Libraries/Core/Timers/JSTimers.js b/packages/react-native/Libraries/Core/Timers/JSTimers.js
index 4ef450e0bc139e..b0b57dfbc23b7d 100644
--- a/packages/react-native/Libraries/Core/Timers/JSTimers.js
+++ b/packages/react-native/Libraries/Core/Timers/JSTimers.js
@@ -11,6 +11,7 @@
 
 import NativeTiming from './NativeTiming';
 
+const toError = require('../../../src/private/utilities/toError').default;
 const BatchedBridge = require('../../BatchedBridge/BatchedBridge').default;
 const Systrace = require('../../Performance/Systrace');
 const invariant = require('invariant');
@@ -129,9 +130,9 @@ function _callTimer(timerID: number, frameTime: number, didTimeout: ?boolean) {
     } else {
       console.error('Tried to call a callback with invalid type: ' + type);
     }
-  } catch (e) {
+  } catch (e: unknown) {
     // Don't rethrow so that we can run all timers.
-    errors.push(e);
+    errors.push(toError(e));
   }
 
   if (__DEV__) {
diff --git a/packages/react-native/Libraries/Core/Timers/__tests__/JSTimers-test.js b/packages/react-native/Libraries/Core/Timers/__tests__/JSTimers-test.js
index 3619fa53d382f4..0f5ebec5ad492d 100644
--- a/packages/react-native/Libraries/Core/Timers/__tests__/JSTimers-test.js
+++ b/packages/react-native/Libraries/Core/Timers/__tests__/JSTimers-test.js
@@ -16,13 +16,10 @@ const NativeTiming = {
   setSendIdleEvents: jest.fn(),
 };
 
-jest
-  .enableAutomock()
-  .mock('../NativeTiming', () => ({
-    __esModule: true,
-    default: NativeTiming,
-  }))
-  .unmock('../JSTimers');
+jest.mock('../NativeTiming', () => ({
+  __esModule: true,
+  default: NativeTiming,
+}));
 
 const JSTimers = require('../JSTimers').default;
 
diff --git a/packages/react-native/Libraries/Core/setUpErrorHandling.js b/packages/react-native/Libraries/Core/setUpErrorHandling.js
index f302c89d83339b..357c12e3bf7989 100644
--- a/packages/react-native/Libraries/Core/setUpErrorHandling.js
+++ b/packages/react-native/Libraries/Core/setUpErrorHandling.js
@@ -16,6 +16,7 @@ if (global.RN$useAlwaysAvailableJSErrorHandling !== true) {
    * You can use this module directly, or just require InitializeCore.
    */
   const ExceptionsManager = require('./ExceptionsManager').default;
+  const toError = require('../../src/private/utilities/toError').default;
   ExceptionsManager.installConsoleErrorReporter();
 
   // Set up error handler
@@ -23,8 +24,9 @@ if (global.RN$useAlwaysAvailableJSErrorHandling !== true) {
     const handleError = (e: unknown, isFatal: boolean) => {
       try {
         ExceptionsManager.handleException(e, isFatal);
-      } catch (ee) {
-        console.log('Failed to print error: ', ee.message);
+      } catch (ee: unknown) {
+        const error = toError(ee);
+        console.log('Failed to print error: ', error.message);
         throw e;
       }
     };
diff --git a/packages/react-native/Libraries/Core/setUpReactDevTools.js b/packages/react-native/Libraries/Core/setUpReactDevTools.js
index 9bdf66b30184b9..d5ed254acdff1e 100644
--- a/packages/react-native/Libraries/Core/setUpReactDevTools.js
+++ b/packages/react-native/Libraries/Core/setUpReactDevTools.js
@@ -49,7 +49,7 @@ if (__DEV__) {
     try {
       const parsedSettings = JSON.parse(serializedHookSettings);
       hookSettings = parsedSettings;
-    } catch {
+    } catch (e: unknown) {
       console.error(
         'Failed to parse persisted React DevTools hook settings. React DevTools will be initialized with default settings.',
       );
diff --git a/packages/react-native/Libraries/Interaction/InteractionManager.js b/packages/react-native/Libraries/Interaction/InteractionManager.js
index 81aae40474da9a..55c4c27e85b0c6 100644
--- a/packages/react-native/Libraries/Interaction/InteractionManager.js
+++ b/packages/react-native/Libraries/Interaction/InteractionManager.js
@@ -10,6 +10,7 @@
 
 import type {EventSubscription} from '../vendor/emitter/EventEmitter';
 
+const toError = require('../../src/private/utilities/toError').default;
 const invariant = require('invariant');
 
 export type SimpleTask = {
@@ -113,8 +114,8 @@ const InteractionManagerStub = {
             try {
               task.run();
               resolve();
-            } catch (error) {
-              reject(error);
+            } catch (error: unknown) {
+              reject(toError(error));
             }
           } else {
             reject(new TypeError(`Task "${task.name}" missing gen or run.`));
@@ -123,8 +124,8 @@ const InteractionManagerStub = {
           try {
             task();
             resolve();
-          } catch (error) {
-            reject(error);
+          } catch (error: unknown) {
+            reject(toError(error));
           }
         } else {
           reject(new TypeError('Invalid task of type: ' + typeof task));
diff --git a/packages/react-native/Libraries/LogBox/Data/LogBoxData.js b/packages/react-native/Libraries/LogBox/Data/LogBoxData.js
index a874864a746af4..277a989a765690 100644
--- a/packages/react-native/Libraries/LogBox/Data/LogBoxData.js
+++ b/packages/react-native/Libraries/LogBox/Data/LogBoxData.js
@@ -19,6 +19,7 @@ import type {
 } from './parseLogBoxLog';
 
 import DebuggerSessionObserver from '../../../src/private/devsupport/rndevtools/FuseboxSessionObserver';
+import toExtendedError from '../../../src/private/utilities/toExtendedError';
 import parseErrorStack from '../../Core/Devtools/parseErrorStack';
 import NativeLogBox from '../../NativeModules/specs/NativeLogBox';
 import LogBoxLog from './LogBoxLog';
@@ -240,8 +241,8 @@ export function addLog(log: LogData): void {
           componentStackType: log.componentStackType || 'legacy',
         }),
       );
-    } catch (error) {
-      reportLogBoxError(error);
+    } catch (error: unknown) {
+      reportLogBoxError(toExtendedError(error));
     }
   });
 }
@@ -252,8 +253,8 @@ export function addException(error: ExtendedExceptionData): void {
   setImmediate(() => {
     try {
       appendNewLog(new LogBoxLog(parseLogBoxException(error)));
-    } catch (loggingError) {
-      reportLogBoxError(loggingError);
+    } catch (loggingError: unknown) {
+      reportLogBoxError(toExtendedError(loggingError));
     }
   });
 }
diff --git a/packages/react-native/Libraries/LogBox/LogBox.js b/packages/react-native/Libraries/LogBox/LogBox.js
index e966de1cb034c8..96ff3ad64b8fbd 100644
--- a/packages/react-native/Libraries/LogBox/LogBox.js
+++ b/packages/react-native/Libraries/LogBox/LogBox.js
@@ -11,6 +11,7 @@
 import type {IgnorePattern, LogData} from './Data/LogBoxData';
 import type {ExtendedExceptionData} from './Data/parseLogBoxLog';
 
+import toExtendedError from '../../src/private/utilities/toExtendedError';
 import Platform from '../Utilities/Platform';
 import RCTLog from '../Utilities/RCTLog';
 import * as React from 'react';
@@ -192,8 +193,8 @@ if (__DEV__) {
               componentStackType,
             });
           }
-        } catch (err) {
-          LogBoxData.reportLogBoxError(err);
+        } catch (err: unknown) {
+          LogBoxData.reportLogBoxError(toExtendedError(err));
         }
       }
     },
@@ -237,8 +238,8 @@ if (__DEV__) {
           });
         }
       }
-    } catch (err) {
-      LogBoxData.reportLogBoxError(err);
+    } catch (err: unknown) {
+      LogBoxData.reportLogBoxError(toExtendedError(err));
     }
   };
 } else {
diff --git a/packages/react-native/Libraries/Network/XMLHttpRequest.js b/packages/react-native/Libraries/Network/XMLHttpRequest.js
index be83740f65ae9a..d097f8a79747e2 100644
--- a/packages/react-native/Libraries/Network/XMLHttpRequest.js
+++ b/packages/react-native/Libraries/Network/XMLHttpRequest.js
@@ -284,7 +284,7 @@ class XMLHttpRequest extends EventTarget {
       case 'json':
         try {
           this._cachedResponse = JSON.parse(this._response);
-        } catch (_) {
+        } catch (_: unknown) {
           this._cachedResponse = null;
         }
         break;
diff --git a/packages/react-native/src/private/utilities/toError.js b/packages/react-native/src/private/utilities/toError.js
new file mode 100644
index 00000000000000..fa1c3c9863cbf4
--- /dev/null
+++ b/packages/react-native/src/private/utilities/toError.js
@@ -0,0 +1,27 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict
+ * @format
+ */
+
+/**
+ * Converts an unknown value to an Error instance.
+ * If the value is already an Error, returns it as-is.
+ * Otherwise, creates a new Error with the stringified value as the message.
+ *
+ * This is particularly useful in catch blocks where the caught value
+ * is annotated as `unknown` but needs to be treated as an Error.
+ *
+ * @param value - The unknown value to convert to an Error
+ * @returns An Error instance
+ */
+export default function toError(value: unknown): Error {
+  if (value instanceof Error) {
+    return value;
+  }
+  return new Error(String(value));
+}
diff --git a/packages/react-native/src/private/utilities/toExtendedError.js b/packages/react-native/src/private/utilities/toExtendedError.js
new file mode 100644
index 00000000000000..988a72796f4586
--- /dev/null
+++ b/packages/react-native/src/private/utilities/toExtendedError.js
@@ -0,0 +1,30 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict
+ * @format
+ */
+
+import type {ExtendedError} from '../../../Libraries/Core/ExtendedError';
+
+import toError from './toError';
+
+/**
+ * Converts an unknown value to an ExtendedError instance suitable for LogBox.
+ * Uses the standard toError utility internally and then casts to ExtendedError.
+ *
+ * This is specifically designed for LogBox error reporting which requires
+ * ExtendedError type compatibility.
+ *
+ * @param value - The unknown value to convert to an ExtendedError
+ * @returns An ExtendedError instance
+ */
+export default function toExtendedError(value: unknown): ExtendedError {
+  const error = toError(value);
+  // ExtendedError extends Error, so this cast is safe for the LogBox system
+  // $FlowFixMe[incompatible-type] ExtendedError extends Error, this cast is safe
+  return (error: ExtendedError);
+}