diff --git a/gestioncof/migrations/0018_django_cas_to_authens.py b/gestioncof/migrations/0018_django_cas_to_authens.py
new file mode 100644
index 00000000..9b689a7e
--- /dev/null
+++ b/gestioncof/migrations/0018_django_cas_to_authens.py
@@ -0,0 +1,40 @@
+import sys
+
+from authens.shortcuts import fetch_cas_account
+from django.db import migrations
+
+
+def to_authens(apps, schema_editor):
+    User = apps.get_model("auth", "User")
+    CASAccount = apps.get_model("authens", "CASAccount")
+
+    failures = []
+    for user in User.objects.select_related("profile").all():
+        login_clipper = user.profile.login_clipper
+        if login_clipper:
+            ldap_info = fetch_cas_account(login_clipper)
+            if ldap_info is None:
+                failures.append(user)
+            else:
+                entrance_year = ldap_info["entrance_year"]
+                CASAccount.objects.create(
+                    user=user, cas_login=login_clipper, entrance_year=entrance_year
+                )
+
+    if failures:
+        sys.stderr.write(" ---------- \n")
+        sys.stderr.write("Some accounts could not be linked to a CAS account:\n")
+        for user in failures:
+            sys.stderr.write(f"- {user.username}\n")
+        sys.stderr.write(" ---------- \n")
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("gestioncof", "0017_petitscours_uniqueness"),
+    ]
+
+    operations = [
+        migrations.RunPython(to_authens, migrations.RunPython.noop),
+    ]