diff --git a/pyproject.toml b/pyproject.toml
index e8a2dc8..cf4e569 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -62,3 +62,6 @@ env = [
   "DATA_SCHEMA_LOCAL=/home/colin/git/decp-processing/dist/schema.json",
 ]
 addopts = "-p no:warnings"
+markers = [
+    "integration: tests touchant des services externes (Brevo) ; skippés par défaut en CI",
+]
diff --git a/tests/auth/test_mailer_integration.py b/tests/auth/test_mailer_integration.py
new file mode 100644
index 0000000..05bd7c8
--- /dev/null
+++ b/tests/auth/test_mailer_integration.py
@@ -0,0 +1,22 @@
+import os
+
+import pytest
+
+from src.auth import mailer
+
+pytestmark = pytest.mark.integration
+
+
+@pytest.mark.skipif(
+    not os.getenv("BREVO_API_KEY"),
+    reason="BREVO_API_KEY absent — test d'intégration Brevo ignoré",
+)
+def test_send_verification_email_sandbox(monkeypatch):
+    # Force le mode sandbox : Brevo valide la requête sans délivrer.
+    monkeypatch.setenv("BREVO_SANDBOX", "true")
+    monkeypatch.setenv("APP_BASE_URL", "http://localhost:8050")
+    mailer.init_mailer()
+    # Ne doit pas lever : l'API Brevo accepte la requête en sandbox.
+    mailer.send_verification_email(
+        os.getenv("MAIL_FROM", "noreply@decp.info"), "INTEGRATION_TOKEN"
+    )