diff --git a/auth0_flutter/lib/auth0_flutter_web.dart b/auth0_flutter/lib/auth0_flutter_web.dart
index 224188fe..cd9e5085 100644
--- a/auth0_flutter/lib/auth0_flutter_web.dart
+++ b/auth0_flutter/lib/auth0_flutter_web.dart
@@ -51,7 +51,8 @@ class Auth0Web {
       final bool? useRefreshTokens,
       final bool? useRefreshTokensFallback,
       final String? audience,
-      final Set<String>? scopes}) async {
+      final Set<String>? scopes,
+      final Map<String, String> parameters = const {}}) async {
     await Auth0FlutterWebPlatform.instance.initialize(
         ClientOptions(
             account: _account,
@@ -68,7 +69,8 @@ class Auth0Web {
             useRefreshTokens: useRefreshTokens,
             useRefreshTokensFallback: useRefreshTokensFallback,
             audience: audience,
-            scopes: scopes),
+            scopes: scopes,
+            parameters: parameters),
         _userAgent);
 
     if (await hasValidCredentials()) {
diff --git a/auth0_flutter/lib/src/web/extensions/client_options_extensions.dart b/auth0_flutter/lib/src/web/extensions/client_options_extensions.dart
index c70a6965..ade2b67c 100644
--- a/auth0_flutter/lib/src/web/extensions/client_options_extensions.dart
+++ b/auth0_flutter/lib/src/web/extensions/client_options_extensions.dart
@@ -21,7 +21,12 @@ extension ClientOptionsExtension on ClientOptions {
           useFormData: useFormData,
           useRefreshTokens: useRefreshTokens,
           useRefreshTokensFallback: useRefreshTokensFallback,
-          authorizationParams: JsInteropUtils.stripNulls(AuthorizationParams(
-              audience: audience,
-              scope: scopes?.isNotEmpty == true ? scopes?.join(' ') : null)));
+          authorizationParams: JsInteropUtils.stripNulls(
+              JsInteropUtils.addCustomParams(
+                  AuthorizationParams(
+                      audience: audience,
+                      scope: scopes?.isNotEmpty == true
+                          ? scopes?.join(' ')
+                          : null),
+                  parameters)));
 }
diff --git a/auth0_flutter_platform_interface/lib/src/web/client_options.dart b/auth0_flutter_platform_interface/lib/src/web/client_options.dart
index e7e11836..77334b62 100644
--- a/auth0_flutter_platform_interface/lib/src/web/client_options.dart
+++ b/auth0_flutter_platform_interface/lib/src/web/client_options.dart
@@ -105,6 +105,9 @@ class ClientOptions {
   /// Note: The openid scope is always applied regardless of this setting.
   final Set<String>? scopes;
 
+  /// The default additional parameters to be sent to Auth0.
+  final Map<String, String> parameters;
+
   ClientOptions(
       {required this.account,
       this.authorizeTimeoutInSeconds,
@@ -119,5 +122,6 @@ class ClientOptions {
       this.useRefreshTokensFallback,
       this.idTokenValidationConfig,
       this.audience,
-      this.scopes});
+      this.scopes,
+      this.parameters = const {}});
 }