diff --git a/frontend/lib/services/user_service.dart b/frontend/lib/services/user_service.dart
index eb67a67..533af83 100644
--- a/frontend/lib/services/user_service.dart
+++ b/frontend/lib/services/user_service.dart
@@ -215,6 +215,30 @@ class UserService {
     return AppUser.fromJson(Map<String, dynamic>.from(data is Map ? data : {}));
   }
 
+  /// Refuser un compte en attente (AM ou parent). PATCH /users/:id/refuser. Ticket #110.
+  static Future<AppUser> refuseUser(String userId, {String? comment}) async {
+    final response = await http.patch(
+      Uri.parse('${ApiConfig.baseUrl}${ApiConfig.users}/$userId/refuser'),
+      headers: await _headers(),
+      body: jsonEncode(
+        comment != null && comment.trim().isNotEmpty
+            ? {'comment': comment.trim()}
+            : {},
+      ),
+    );
+    if (response.statusCode != 200) {
+      try {
+        final err = jsonDecode(response.body);
+        throw Exception(_errMessage(err is Map ? err['message'] : err));
+      } catch (e) {
+        if (e is Exception) rethrow;
+        throw Exception('Erreur refus (${response.statusCode})');
+      }
+    }
+    final data = jsonDecode(response.body);
+    return AppUser.fromJson(Map<String, dynamic>.from(data is Map ? data : {}));
+  }
+
   /// Valider tout le dossier famille. POST /parents/:parentId/valider-dossier. Ticket #108.
   static Future<List<AppUser>> validerDossierFamille(String parentId, {String? comment}) async {
     final response = await http.post(
diff --git a/frontend/lib/widgets/admin/validation_am_wizard.dart b/frontend/lib/widgets/admin/validation_am_wizard.dart
index d910db5..991ef24 100644
--- a/frontend/lib/widgets/admin/validation_am_wizard.dart
+++ b/frontend/lib/widgets/admin/validation_am_wizard.dart
@@ -480,15 +480,12 @@ class _ValidationAmWizardState extends State<ValidationAmWizard> {
         children: [
           Expanded(
             child: ValidationRefusForm(
+              isSubmitting: _submitting,
               onCancel: widget.onClose,
               onPrevious: () => setState(() => _showRefusForm = false),
               onSubmit: (comment) {
-                if (!mounted) return;
-                ScaffoldMessenger.of(context).showSnackBar(
-                  const SnackBar(
-                      content: Text('Refus (à brancher sur l’API refus)')),
-                );
-                widget.onClose();
+                if (comment == null || comment.trim().isEmpty) return;
+                _refuserEnvoyer(comment.trim());
               },
             ),
           ),
@@ -496,4 +493,26 @@ class _ValidationAmWizardState extends State<ValidationAmWizard> {
       ),
     );
   }
+
+  Future<void> _refuserEnvoyer(String comment) async {
+    if (_submitting) return;
+    setState(() => _submitting = true);
+    try {
+      await UserService.refuseUser(widget.dossier.user.id, comment: comment);
+      if (!mounted) return;
+      widget.onSuccess();
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(e is Exception
+              ? e.toString().replaceFirst('Exception: ', '')
+              : 'Erreur'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+    } finally {
+      if (mounted) setState(() => _submitting = false);
+    }
+  }
 }
diff --git a/frontend/lib/widgets/admin/validation_family_wizard.dart b/frontend/lib/widgets/admin/validation_family_wizard.dart
index 2178bf5..27972e2 100644
--- a/frontend/lib/widgets/admin/validation_family_wizard.dart
+++ b/frontend/lib/widgets/admin/validation_family_wizard.dart
@@ -697,16 +697,12 @@ class _ValidationFamilyWizardState extends State<ValidationFamilyWizard> {
         children: [
           Expanded(
             child: ValidationRefusForm(
+              isSubmitting: _submitting,
               onCancel: widget.onClose,
               onPrevious: () => setState(() => _showRefusForm = false),
               onSubmit: (comment) {
-                if (!mounted) return;
-                ScaffoldMessenger.of(context).showSnackBar(
-                  const SnackBar(
-                      content: Text(
-                          'Refus (à brancher sur l’API refus – ticket #110)')),
-                );
-                widget.onClose();
+                if (comment == null || comment.trim().isEmpty) return;
+                _refuserEnvoyer(comment.trim());
               },
             ),
           ),
@@ -714,4 +710,42 @@ class _ValidationFamilyWizardState extends State<ValidationFamilyWizard> {
       ),
     );
   }
+
+  /// Refuse chaque parent encore `en_attente` (même commentaire, e-mail reprise par compte). Ticket #110.
+  Future<void> _refuserEnvoyer(String comment) async {
+    if (_submitting) return;
+    final pending = widget.dossier.parents
+        .where((p) => p.statut == 'en_attente' && p.id.trim().isNotEmpty)
+        .toList();
+    if (pending.isEmpty) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: const Text('Aucun compte en attente à refuser pour ce dossier.'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+      return;
+    }
+    setState(() => _submitting = true);
+    try {
+      for (final p in pending) {
+        await UserService.refuseUser(p.id, comment: comment);
+      }
+      if (!mounted) return;
+      widget.onSuccess();
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(e is Exception
+              ? e.toString().replaceFirst('Exception: ', '')
+              : 'Erreur'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+    } finally {
+      if (mounted) setState(() => _submitting = false);
+    }
+  }
 }
diff --git a/frontend/lib/widgets/admin/validation_refus_form.dart b/frontend/lib/widgets/admin/validation_refus_form.dart
index e2d6285..3eb9d3a 100644
--- a/frontend/lib/widgets/admin/validation_refus_form.dart
+++ b/frontend/lib/widgets/admin/validation_refus_form.dart
@@ -8,12 +8,15 @@ class ValidationRefusForm extends StatefulWidget {
   /// Retour à l’étape précédente du wizard (écran avec Valider / Refuser).
   final VoidCallback onPrevious;
   final ValueChanged<String?> onSubmit;
+  /// Pendant l'appel API : désactive les actions (ticket #110).
+  final bool isSubmitting;
 
   const ValidationRefusForm({
     super.key,
     required this.onCancel,
     required this.onPrevious,
     required this.onSubmit,
+    this.isSubmitting = false,
   });
 
   @override
@@ -67,6 +70,7 @@ class _ValidationRefusFormState extends State<ValidationRefusForm> {
                   ),
                   child: TextFormField(
                     controller: _controller,
+                    readOnly: widget.isSubmitting,
                     maxLines: null,
                     minLines: 1,
                     validator: _validateMotifs,
@@ -91,7 +95,7 @@ class _ValidationRefusFormState extends State<ValidationRefusForm> {
           Row(
             children: [
               TextButton(
-                onPressed: widget.onCancel,
+                onPressed: widget.isSubmitting ? null : widget.onCancel,
                 child: const Text('Annuler'),
               ),
               const Spacer(),
@@ -99,19 +103,29 @@ class _ValidationRefusFormState extends State<ValidationRefusForm> {
                 mainAxisSize: MainAxisSize.min,
                 children: [
                   TextButton(
-                    onPressed: widget.onPrevious,
+                    onPressed: widget.isSubmitting ? null : widget.onPrevious,
                     child: const Text('Précédent'),
                   ),
                   const SizedBox(width: 8),
-                  ElevatedButton(
-                    style: ValidationModalTheme.primaryElevatedStyle,
-                    onPressed: () {
-                      if (_formKey.currentState!.validate()) {
-                        widget.onSubmit(_controller.text.trim());
-                      }
-                    },
-                    child: const Text('Envoyer'),
-                  ),
+                  if (widget.isSubmitting)
+                    const Padding(
+                      padding: EdgeInsets.symmetric(horizontal: 12),
+                      child: SizedBox(
+                        width: 22,
+                        height: 22,
+                        child: CircularProgressIndicator(strokeWidth: 2),
+                      ),
+                    )
+                  else
+                    ElevatedButton(
+                      style: ValidationModalTheme.primaryElevatedStyle,
+                      onPressed: () {
+                        if (_formKey.currentState!.validate()) {
+                          widget.onSubmit(_controller.text.trim());
+                        }
+                      },
+                      child: const Text('Envoyer'),
+                    ),
                 ],
               ),
             ],