diff --git a/frontend/lib/screens/auth/am_register_step4_screen.dart b/frontend/lib/screens/auth/am_register_step4_screen.dart
index 6d97e45..93c0bf7 100644
--- a/frontend/lib/screens/auth/am_register_step4_screen.dart
+++ b/frontend/lib/screens/auth/am_register_step4_screen.dart
@@ -7,6 +7,7 @@ import 'dart:math' as math;
 import '../../models/am_registration_data.dart';
 import '../../models/card_assets.dart';
 import '../../config/display_config.dart';
+import '../../services/auth_service.dart';
 import '../../widgets/hover_relief_widget.dart';
 import '../../widgets/image_button.dart';
 import '../../widgets/custom_navigation_button.dart';
@@ -22,6 +23,28 @@ class AmRegisterStep4Screen extends StatefulWidget {
 }
 
 class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
+  bool _isSubmitting = false;
+
+  Future<void> _submitAMRegistration(AmRegistrationData registrationData) async {
+    if (_isSubmitting) return;
+    setState(() => _isSubmitting = true);
+    try {
+      await AuthService.registerAM(registrationData);
+      if (!mounted) return;
+      _showConfirmationModal(context);
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(e is Exception ? e.toString().replaceFirst('Exception: ', '') : 'Erreur lors de l\'inscription'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+    } finally {
+      if (mounted) setState(() => _isSubmitting = false);
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     final registrationData = Provider.of<AmRegistrationData>(context);
@@ -90,12 +113,9 @@ class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
                             Expanded(
                               child: HoverReliefWidget(
                                 child: CustomNavigationButton(
-                                  text: 'Soumettre',
+                                  text: _isSubmitting ? 'Envoi...' : 'Soumettre',
                                   style: NavigationButtonStyle.green,
-                                  onPressed: () {
-                                    print("Données AM finales: ${registrationData.firstName} ${registrationData.lastName}");
-                                    _showConfirmationModal(context);
-                                  },
+                                  onPressed: () => _submitAMRegistration(registrationData),
                                   width: double.infinity,
                                   height: 50,
                                   fontSize: 16,
@@ -106,17 +126,14 @@ class _AmRegisterStep4ScreenState extends State<AmRegisterStep4Screen> {
                         ),
                       )
                     else
-                      ImageButton(
+                        ImageButton(
                         bg: 'assets/images/bg_green.png',
-                        text: 'Soumettre ma demande',
+                        text: _isSubmitting ? 'Envoi...' : 'Soumettre ma demande',
                         textColor: const Color(0xFF2D6A4F),
                         width: 350,
                         height: 50,
                         fontSize: 18,
-                        onPressed: () {
-                          print("Données AM finales: ${registrationData.firstName} ${registrationData.lastName}");
-                          _showConfirmationModal(context);
-                        },
+                        onPressed: () => _submitAMRegistration(registrationData),
                       ),
                   ],
                 ),
diff --git a/frontend/lib/services/auth_service.dart b/frontend/lib/services/auth_service.dart
index 7a44678..f9b0e75 100644
--- a/frontend/lib/services/auth_service.dart
+++ b/frontend/lib/services/auth_service.dart
@@ -1,9 +1,12 @@
 import 'dart:convert';
+import 'dart:io';
 import 'package:http/http.dart' as http;
 import 'package:shared_preferences/shared_preferences.dart';
 import '../models/user.dart';
+import '../models/am_registration_data.dart';
 import 'api/api_config.dart';
 import 'api/tokenService.dart';
+import '../utils/nir_utils.dart';
 
 class AuthService {
   static const String _currentUserKey = 'current_user';
@@ -133,6 +136,70 @@ class AuthService {
     await prefs.setString(_currentUserKey, jsonEncode(user.toJson()));
   }
 
+  /// Inscription AM complète (POST /auth/register/am).
+  /// En cas de succès (201), aucune donnée utilisateur retournée ; rediriger vers login.
+  static Future<void> registerAM(AmRegistrationData data) async {
+    String? photoBase64;
+    if (data.photoPath != null && data.photoPath!.isNotEmpty && !data.photoPath!.startsWith('assets/')) {
+      try {
+        final file = File(data.photoPath!);
+        if (await file.exists()) {
+          final bytes = await file.readAsBytes();
+          photoBase64 = 'data:image/jpeg;base64,${base64Encode(bytes)}';
+        }
+      } catch (_) {}
+    }
+
+    final body = {
+      'email': data.email,
+      'prenom': data.firstName,
+      'nom': data.lastName,
+      'telephone': data.phone,
+      'adresse': data.streetAddress.isNotEmpty ? data.streetAddress : null,
+      'code_postal': data.postalCode.isNotEmpty ? data.postalCode : null,
+      'ville': data.city.isNotEmpty ? data.city : null,
+      if (photoBase64 != null) 'photo_base64': photoBase64,
+      'consentement_photo': data.photoConsent,
+      'date_naissance': data.dateOfBirth != null
+          ? '${data.dateOfBirth!.year}-${data.dateOfBirth!.month.toString().padLeft(2, '0')}-${data.dateOfBirth!.day.toString().padLeft(2, '0')}'
+          : null,
+      'lieu_naissance_ville': data.birthCity.isNotEmpty ? data.birthCity : null,
+      'lieu_naissance_pays': data.birthCountry.isNotEmpty ? data.birthCountry : null,
+      'nir': normalizeNir(data.nir),
+      'numero_agrement': data.agrementNumber,
+      'capacite_accueil': data.capacity ?? 1,
+      'biographie': data.presentationText.isNotEmpty ? data.presentationText : null,
+      'acceptation_cgu': data.cguAccepted,
+      'acceptation_privacy': data.cguAccepted,
+    };
+
+    final response = await http.post(
+      Uri.parse('${ApiConfig.baseUrl}${ApiConfig.registerAM}'),
+      headers: ApiConfig.headers,
+      body: jsonEncode(body),
+    );
+
+    if (response.statusCode == 200 || response.statusCode == 201) {
+      return;
+    }
+
+    final decoded = response.body.isNotEmpty ? jsonDecode(response.body) : null;
+    final message = _extractErrorMessage(decoded, response.statusCode);
+    throw Exception(message);
+  }
+
+  /// Extrait le message d'erreur des réponses NestJS (message string, array, ou objet).
+  static String _extractErrorMessage(dynamic decoded, int statusCode) {
+    const fallback = 'Erreur lors de l\'inscription';
+    if (decoded == null || decoded is! Map) return '$fallback ($statusCode)';
+    final msg = decoded['message'];
+    if (msg == null) return decoded['error'] as String? ?? '$fallback ($statusCode)';
+    if (msg is String) return msg;
+    if (msg is List) return msg.map((e) => e.toString()).join('. ').trim();
+    if (msg is Map && msg['message'] != null) return msg['message'].toString();
+    return '$fallback ($statusCode)';
+  }
+
   /// Rafraîchit le profil utilisateur depuis l'API
   static Future<AppUser?> refreshCurrentUser() async {
     final token = await TokenService.getToken();
diff --git a/frontend/lib/utils/nir_utils.dart b/frontend/lib/utils/nir_utils.dart
index ea8d072..cfed04b 100644
--- a/frontend/lib/utils/nir_utils.dart
+++ b/frontend/lib/utils/nir_utils.dart
@@ -49,15 +49,11 @@ String nirToRaw(String normalized) {
   return s;
 }
 
-/// Formate pour affichage : 1 12 34 56 789 012-34 ou 1 12 34 2A 789 012-34
+/// Formate pour affichage : 1 12 34 56 789 012-34 ou 1 12 34 2A 789 012-34 (Corse).
 String formatNir(String raw) {
   final r = nirToRaw(raw);
   if (r.length < 15) return r;
-  final dept = r.substring(5, 7);
-  final isCorsica = dept == '2A' || dept == '2B';
-  if (isCorsica) {
-    return '${r.substring(0, 5)} ${r.substring(5, 7)} ${r.substring(7, 10)} ${r.substring(10, 13)}-${r.substring(13, 15)}';
-  }
+  // Même structure pour tous : sexe + année + mois + département + commune + ordre-clé.
   return '${r.substring(0, 1)} ${r.substring(1, 3)} ${r.substring(3, 5)} ${r.substring(5, 7)} ${r.substring(7, 10)} ${r.substring(10, 13)}-${r.substring(13, 15)}';
 }
 
@@ -67,7 +63,7 @@ bool _isFormatValid(String raw) {
   final dept = raw.substring(5, 7);
   final restDigits = raw.substring(0, 5) + (dept == '2A' ? '19' : dept == '2B' ? '18' : dept) + raw.substring(7, 15);
   if (!RegExp(r'^[12]\d{12}\d{2}$').hasMatch(restDigits)) return false;
-  return RegExp(r'^[12]\d{4}(?:\d{2}|2A|2B)\d{6}$').hasMatch(raw);
+  return RegExp(r'^[12]\d{4}(?:\d{2}|2A|2B)\d{8}$').hasMatch(raw);
 }
 
 /// Calcule la clé de contrôle (97 - (NIR13 mod 97)). Pour 2A→19, 2B→18.