diff --git a/lemarche/siaes/models.py b/lemarche/siaes/models.py
index 05a478b21..224f7fa2a 100644
--- a/lemarche/siaes/models.py
+++ b/lemarche/siaes/models.py
@@ -1040,6 +1040,21 @@ def completion_percent(self):
         score_percent = round(score / total, 2) * 100
         return round_by_base(score_percent, base=5)
 
+    @property
+    def latest_activity_at(self):
+        latest_activity_at = None
+        users_activity = self.users.annotate(
+            latest_activity_at=Greatest(
+                "updated_at", "last_login", "dashboard_last_seen_date", "tender_list_last_seen_date"
+            )
+        ).order_by("-latest_activity_at")
+        if users_activity:
+            latest_activity_at = users_activity.first().latest_activity_at
+            latest_activity_at = self.updated_at if self.updated_at > latest_activity_at else latest_activity_at
+        else:
+            latest_activity_at = self.updated_at
+        return latest_activity_at
+
     def sectors_list_string(self, display_max=3):
         sectors_name_list = self.sectors.form_filter_queryset().values_list("name", flat=True)
         if display_max and len(sectors_name_list) > display_max:
diff --git a/lemarche/siaes/tests.py b/lemarche/siaes/tests.py
index f1c2194e2..8259bdb6f 100644
--- a/lemarche/siaes/tests.py
+++ b/lemarche/siaes/tests.py
@@ -480,3 +480,22 @@ def setUpTestData(cls):
 
     def test_calculate_etablissement_count(self):
         self.assertEqual(siae_utils.calculate_etablissement_count(self.siae_with_siret_1), 2)
+
+
+class SiaeActivitiesTest(TestCase):
+    @classmethod
+    def setUpTestData(cls) -> None:
+        # cls.users = [UserFactory() for i in range(3)]
+        cls.siae: Siae = SiaeFactory(siret="12312312312345", is_active=True)
+
+    def test_last_activity_is_updated_at(self):
+        self.assertEqual(self.siae.updated_at, self.siae.latest_activity_at)
+        users = [UserFactory() for i in range(3)]
+        self.siae.users.set(users)
+        users[0].first_name = "test"
+        users[0].save()
+        self.assertNotEqual(self.siae.updated_at, self.siae.latest_activity_at)
+        self.assertTrue(self.siae.updated_at < self.siae.latest_activity_at)
+        self.siae.name = "test_siae"
+        self.siae.save()
+        self.assertTrue(self.siae.updated_at == self.siae.latest_activity_at)
diff --git a/lemarche/templates/siaes/_card_detail.html b/lemarche/templates/siaes/_card_detail.html
index ad27a9b79..27705bfc7 100644
--- a/lemarche/templates/siaes/_card_detail.html
+++ b/lemarche/templates/siaes/_card_detail.html
@@ -16,7 +16,7 @@
                         <h1 class="h2 mb-2">
                             {{ siae.name_display }}
                             <br />
-                            <small>(profil mis à jour il y a {{ siae.updated_at|timesince }})</small>
+                            <small>(Dernière activité il y a {{ siae.latest_activity_at|timesince }})</small>
                         </h1>
                         {% if user.is_authenticated %}
                             {% if siae.in_user_favorite_list_count %}
diff --git a/lemarche/users/models.py b/lemarche/users/models.py
index ce623b56b..4018127b1 100644
--- a/lemarche/users/models.py
+++ b/lemarche/users/models.py
@@ -4,7 +4,7 @@
 from django.contrib.contenttypes.fields import GenericRelation
 from django.db import models
 from django.db.models import Count
-from django.db.models.functions import Lower
+from django.db.models.functions import Greatest, Lower
 from django.db.models.signals import post_save
 from django.dispatch import receiver
 from django.forms.models import model_to_dict
@@ -44,6 +44,13 @@ def with_siae_stats(self):
     def with_tender_stats(self):
         return self.prefetch_related("tenders").annotate(tender_count=Count("tenders", distinct=True))
 
+    def with_latest_activities(self):
+        return self.annotate(
+            latest_activity_at=Greatest(
+                "updated_at", "last_login", "dashboard_last_seen_date", "tender_list_last_seen_date"
+            )
+        )
+
 
 class UserManager(BaseUserManager):
     """