diff --git a/backend/app/routes/billing.py b/backend/app/routes/billing.py
index 5764bf41..1a52124f 100644
--- a/backend/app/routes/billing.py
+++ b/backend/app/routes/billing.py
@@ -147,11 +147,11 @@ async def stripe_webhook():
             logger.info("Skipping unpaid checkout session %s", session.id)
             return jsonify({"status": "ok"}), 200
 
-        # metadata is a plain dict in the Stripe SDK
-        meta = dict(session.metadata) if session.metadata else {}
-        user_id = meta.get("user_id")
-        credits = int(meta.get("credits", 0))
-        pack_id = meta.get("pack_id", "")
+        # metadata is a StripeObject in SDK v5 — use attribute access
+        meta = session.metadata
+        user_id = getattr(meta, "user_id", None) if meta else None
+        credits = int(getattr(meta, "credits", 0) or 0) if meta else 0
+        pack_id = getattr(meta, "pack_id", "") if meta else ""
         # `or` so explicit null payment_intent falls through to session id
         payment_id = session.payment_intent or session.id