diff --git a/backend/app/api/routes/events/guests.py b/backend/app/api/routes/events/guests.py
index fb48cad..45f540e 100644
--- a/backend/app/api/routes/events/guests.py
+++ b/backend/app/api/routes/events/guests.py
@@ -87,7 +87,8 @@ def process_guest_rsvp(
 
         # Update guest status to match RSVP
         guest_status = map_rsvp_status_to_guest_status(rsvp_data.status)
-        guest = guest_crud.update_status(db, guest_id=guest_id, status=guest_status, number_of_guests=rsvp_data.number_of_guests or 0)
+        additional_guests = max(0, rsvp_data.number_of_guests - 1)
+        guest = guest_crud.update_status(db, guest_id=guest_id, status=guest_status, number_of_guests=additional_guests)
 
         # Both operations succeeded, commit the transaction
         db.commit()