diff --git a/app/modules/loyalty/templates/loyalty/store/enroll.html b/app/modules/loyalty/templates/loyalty/store/enroll.html
index e1a981ef..c395a911 100644
--- a/app/modules/loyalty/templates/loyalty/store/enroll.html
+++ b/app/modules/loyalty/templates/loyalty/store/enroll.html
@@ -9,6 +9,11 @@
 
 {% block alpine_data %}storeLoyaltyEnroll(){% endblock %}
 
+{% block extra_head %}
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/flatpickr/dist/flatpickr.min.css">
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/flatpickr/dist/themes/dark.css" media="(prefers-color-scheme: dark)">
+{% endblock %}
+
 {% block content %}
 {% call detail_page_header("'" + _('loyalty.store.enroll.page_title') + "'", '/store/' + store_code + '/loyalty/terminal') %}
     {{ _('loyalty.store.enroll.subtitle') }}
@@ -58,7 +63,21 @@
 
                 <div>
                     <label class="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-2">{{ _('loyalty.store.enroll.birthday') }}</label>
-                    <input type="date" x-model="form.birthday"
+                    {# flatpickr instead of <input type="date"> — Firefox ignores
+                       the html lang attribute for native date inputs. dd/mm/yyyy
+                       universally accepted in Europe. #}
+                    <input type="text" x-model="form.birthday"
+                           placeholder="dd/mm/yyyy"
+                           x-init="flatpickr($el, {
+                               dateFormat: 'Y-m-d',
+                               altInput: true,
+                               altFormat: 'd/m/Y',
+                               allowInput: true,
+                               maxDate: 'today',
+                               locale: '{{ current_language|default('en') }}',
+                               disableMobile: false,
+                               onChange: function(selectedDates, dateStr) { form.birthday = dateStr; }
+                           })"
                            class="w-full px-4 py-2 text-sm border border-gray-300 dark:border-gray-600 rounded-lg focus:border-purple-400 focus:outline-none dark:bg-gray-700 dark:text-gray-300">
                     <p class="mt-1 text-xs text-gray-500">{{ _('loyalty.store.enroll.birthday_help') }}</p>
                 </div>
@@ -147,5 +166,10 @@
 {% endblock %}
 
 {% block extra_scripts %}
+{# flatpickr loaded synchronously so x-init can call flatpickr() during Alpine setup #}
+<script src="https://cdn.jsdelivr.net/npm/flatpickr"></script>
+{% if current_language and current_language != 'en' %}
+<script src="https://cdn.jsdelivr.net/npm/flatpickr/dist/l10n/{{ current_language }}.js"></script>
+{% endif %}
 <script defer src="{{ static_v(request, 'loyalty_static', path='store/js/loyalty-enroll.js') }}"></script>
 {% endblock %}
diff --git a/app/modules/loyalty/templates/loyalty/storefront/enroll.html b/app/modules/loyalty/templates/loyalty/storefront/enroll.html
index d6538bb6..7deea81e 100644
--- a/app/modules/loyalty/templates/loyalty/storefront/enroll.html
+++ b/app/modules/loyalty/templates/loyalty/storefront/enroll.html
@@ -7,6 +7,11 @@
 
 {% block alpine_data %}customerLoyaltyEnroll(){% endblock %}
 
+{% block extra_head %}
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/flatpickr/dist/flatpickr.min.css">
+<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/flatpickr/dist/themes/dark.css" media="(prefers-color-scheme: dark)">
+{% endblock %}
+
 {% block content %}
 <div class="min-h-screen flex items-center justify-center px-4 py-12 bg-gray-50 dark:bg-gray-900">
     <div class="max-w-md w-full">
@@ -84,7 +89,22 @@
                     <label class="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-1">
                         {{ _('loyalty.enrollment.form.birthday') }}
                     </label>
-                    <input type="date" x-model="form.birthday"
+                    {# Use flatpickr instead of <input type="date"> — Firefox ignores
+                       the html lang attribute for native date inputs, so users on FR
+                       still saw mm/dd/yyyy. flatpickr enforces dd/mm/yyyy across all
+                       browsers and locales (universal in Europe). #}
+                    <input type="text" x-model="form.birthday"
+                           placeholder="dd/mm/yyyy"
+                           x-init="flatpickr($el, {
+                               dateFormat: 'Y-m-d',
+                               altInput: true,
+                               altFormat: 'd/m/Y',
+                               allowInput: true,
+                               maxDate: 'today',
+                               locale: '{{ current_language|default('en') }}',
+                               disableMobile: false,
+                               onChange: function(selectedDates, dateStr) { form.birthday = dateStr; }
+                           })"
                            class="w-full px-4 py-3 border border-gray-300 dark:border-gray-600 rounded-lg focus:ring-2 focus:ring-primary focus:border-transparent dark:bg-gray-700 dark:text-white">
                     <p class="mt-1 text-xs text-gray-500">{{ _('loyalty.enrollment.form.birthday_hint') }}</p>
                 </div>
@@ -170,5 +190,10 @@
 {% endblock %}
 
 {% block extra_scripts %}
+{# flatpickr loaded synchronously so x-init can call flatpickr() during Alpine setup #}
+<script src="https://cdn.jsdelivr.net/npm/flatpickr"></script>
+{% if current_language and current_language != 'en' %}
+<script src="https://cdn.jsdelivr.net/npm/flatpickr/dist/l10n/{{ current_language }}.js"></script>
+{% endif %}
 <script defer src="{{ static_v(request, 'loyalty_static', path='storefront/js/loyalty-enroll.js') }}"></script>
 {% endblock %}