diff --git a/packages/app-check/__tests__/appcheck.test.ts b/packages/app-check/__tests__/appcheck.test.ts
index 581cc123c4..496fa6a513 100644
--- a/packages/app-check/__tests__/appcheck.test.ts
+++ b/packages/app-check/__tests__/appcheck.test.ts
@@ -1,4 +1,5 @@
-import { describe, expect, it } from '@jest/globals';
+import { describe, expect, it, beforeEach, afterEach } from '@jest/globals';
+import { Platform } from 'react-native';
 
 import {
   initializeAppCheck,
@@ -26,6 +27,74 @@ describe('appCheck()', function () {
       );
     });
 
+    describe('provider name validation', function () {
+      it('throws on invalid android provider name', function () {
+        const provider = new ReactNativeFirebaseAppCheckProvider();
+        provider.configure({
+          android: { provider: 'invalidProvider' as any },
+        });
+        expect(() => initializeAppCheck(undefined, { provider })).toThrow(
+          'Invalid App Check provider "invalidProvider". Valid android providers are: debug, playIntegrity.',
+        );
+      });
+
+      it('does not throw validation error for valid android provider names', function () {
+        for (const name of ['debug', 'playIntegrity']) {
+          const provider = new ReactNativeFirebaseAppCheckProvider();
+          provider.configure({
+            android: { provider: name as any },
+          });
+          try {
+            initializeAppCheck(undefined, { provider });
+          } catch (e: any) {
+            expect(e.message).not.toContain('Invalid App Check provider');
+          }
+        }
+      });
+
+      describe('apple platform', function () {
+        let originalOS: string;
+
+        beforeEach(function () {
+          originalOS = Platform.OS;
+          Platform.OS = 'ios' as any;
+        });
+
+        afterEach(function () {
+          Platform.OS = originalOS as any;
+        });
+
+        it('throws on invalid apple provider name', function () {
+          const provider = new ReactNativeFirebaseAppCheckProvider();
+          provider.configure({
+            apple: { provider: 'appAttestWithDebugProviderFallback' as any },
+          });
+          expect(() => initializeAppCheck(undefined, { provider })).toThrow(
+            'Invalid App Check provider "appAttestWithDebugProviderFallback". Valid apple providers are: debug, deviceCheck, appAttest, appAttestWithDeviceCheckFallback.',
+          );
+        });
+
+        it('does not throw validation error for valid apple provider names', function () {
+          for (const name of [
+            'debug',
+            'deviceCheck',
+            'appAttest',
+            'appAttestWithDeviceCheckFallback',
+          ]) {
+            const provider = new ReactNativeFirebaseAppCheckProvider();
+            provider.configure({
+              apple: { provider: name as any },
+            });
+            try {
+              initializeAppCheck(undefined, { provider });
+            } catch (e: any) {
+              expect(e.message).not.toContain('Invalid App Check provider');
+            }
+          }
+        });
+      });
+    });
+
     it('`getToken` function is properly exposed to end user', function () {
       expect(getToken).toBeDefined();
     });
diff --git a/packages/app-check/android/src/main/java/io/invertase/firebase/appcheck/ReactNativeFirebaseAppCheckProvider.java b/packages/app-check/android/src/main/java/io/invertase/firebase/appcheck/ReactNativeFirebaseAppCheckProvider.java
index 730b1ad0aa..f56d6b628a 100644
--- a/packages/app-check/android/src/main/java/io/invertase/firebase/appcheck/ReactNativeFirebaseAppCheckProvider.java
+++ b/packages/app-check/android/src/main/java/io/invertase/firebase/appcheck/ReactNativeFirebaseAppCheckProvider.java
@@ -89,6 +89,15 @@ public String getDebugSecret() {
       if ("playIntegrity".equals(providerName)) {
         delegateProvider = PlayIntegrityAppCheckProviderFactory.getInstance().create(app);
       }
+
+      if (delegateProvider == null) {
+        String message =
+            "Unknown provider name \""
+                + providerName
+                + "\". Valid providers are: debug, playIntegrity.";
+        Log.e(LOGTAG, message);
+        throw new IllegalArgumentException(message);
+      }
     } catch (Exception e) {
       // This will bubble up and result in a rejected promise with the underlying message
       throw new RuntimeException(e.getMessage());
diff --git a/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckModule.mm b/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckModule.mm
index f3027d9fe9..6d8bcbe890 100644
--- a/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckModule.mm
+++ b/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckModule.mm
@@ -76,10 +76,18 @@ - (void)configureProvider:(NSString *)appName
   FIRApp *firebaseApp = [RCTConvert firAppFromString:appName];
   DLog(@"appName/providerName/debugToken: %@/%@/%@", firebaseApp.name, providerName,
        (debugToken == nil ? @"null" : @"(not shown)"));
-  [[RNFBAppCheckModule sharedInstance].providerFactory configure:firebaseApp
-                                                    providerName:providerName
-                                                      debugToken:debugToken];
-  resolve([NSNull null]);
+  @try {
+    [[RNFBAppCheckModule sharedInstance].providerFactory configure:firebaseApp
+                                                      providerName:providerName
+                                                        debugToken:debugToken];
+    resolve([NSNull null]);
+  } @catch (NSException *exception) {
+    [RNFBSharedUtils rejectPromiseWithUserInfo:reject
+                                      userInfo:(NSMutableDictionary *)@{
+                                        @"code" : @"unknown",
+                                        @"message" : exception.reason ?: @"internal-error",
+                                      }];
+  }
 }
 
 - (void)setTokenAutoRefreshEnabled:(NSString *)appName
diff --git a/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckProvider.m b/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckProvider.m
index 07c3ace612..12a24541fa 100644
--- a/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckProvider.m
+++ b/packages/app-check/ios/RNFBAppCheck/RNFBAppCheckProvider.m
@@ -36,7 +36,8 @@ - (void)configure:(FIRApp *)app
 
   DLog(@"appName %@", app.name);
 
-  // - determine if debugToken is provided via nullable arg
+  self.delegateProvider = nil;
+
   if ([providerName isEqualToString:@"debug"]) {
     // The firebase-ios-sdk debug app check provider will take a token from environment if it
     // exists:
@@ -73,6 +74,15 @@ - (void)configure:(FIRApp *)app
       self.delegateProvider = [[FIRDeviceCheckProvider alloc] initWithApp:app];
     }
   }
+
+  if (self.delegateProvider == nil) {
+    NSString *message =
+        [NSString stringWithFormat:@"Unknown provider name \"%@\". Valid providers are: debug, "
+                                    "deviceCheck, appAttest, appAttestWithDeviceCheckFallback.",
+                                   providerName ?: @"(null)"];
+    NSLog(@"RNFBAppCheck: %@", message);
+    @throw [NSException exceptionWithName:@"RNFBAppCheckException" reason:message userInfo:nil];
+  }
 }
 
 - (void)getTokenWithCompletion:(nonnull void (^)(FIRAppCheckToken *_Nullable,
diff --git a/packages/app-check/lib/index.ts b/packages/app-check/lib/index.ts
index 6a5d8d1517..a96de4f1fe 100644
--- a/packages/app-check/lib/index.ts
+++ b/packages/app-check/lib/index.ts
@@ -49,6 +49,14 @@ import { ReactNativeFirebaseAppCheckProvider } from './providers';
 
 const nativeModuleName = 'NativeRNFBTurboAppCheck';
 
+const VALID_APPLE_PROVIDERS = [
+  'debug',
+  'deviceCheck',
+  'appAttest',
+  'appAttestWithDeviceCheckFallback',
+];
+const VALID_ANDROID_PROVIDERS = ['debug', 'playIntegrity'];
+
 /**
  * Type guard to check if a provider has providerOptions.
  * This provides proper type narrowing for providers that support platform-specific configuration.
@@ -63,6 +71,29 @@ function hasProviderOptions(
   );
 }
 
+function validateProviderName(options: AppCheckOptions): void {
+  if (!hasProviderOptions(options.provider)) {
+    return;
+  }
+  const provider = options.provider;
+  if (Platform.OS === 'android') {
+    const name = provider.providerOptions?.android?.provider;
+    if (isString(name) && !VALID_ANDROID_PROVIDERS.includes(name)) {
+      throw new Error(
+        `Invalid App Check provider "${name}". Valid android providers are: ${VALID_ANDROID_PROVIDERS.join(', ')}.`,
+      );
+    }
+  }
+  if (Platform.OS === 'ios' || Platform.OS === 'macos') {
+    const name = provider.providerOptions?.apple?.provider;
+    if (isString(name) && !VALID_APPLE_PROVIDERS.includes(name)) {
+      throw new Error(
+        `Invalid App Check provider "${name}". Valid apple providers are: ${VALID_APPLE_PROVIDERS.join(', ')}.`,
+      );
+    }
+  }
+}
+
 class FirebaseAppCheckModule extends FirebaseModule<typeof nativeModuleName> {
   _listenerCount: number;
 
@@ -267,6 +298,7 @@ export function initializeAppCheck(app?: FirebaseApp, options?: AppCheckOptions)
   if (!isObject(options)) {
     throw new Error('Invalid configuration: no options defined.');
   }
+  validateProviderName(options);
   const appCheck = getModularAppCheck(app);
   void (appCheck as AppCheckInternal).initializeAppCheck(options);
   return appCheck;