Yes, KLM allows you to reserve a flight without paying immediately, but the reservation is typically held for a limited time. The option to hold a reservation is available through KLM’s booking system and can be useful if you need extra time to make a decision or finalize your plans. However, after the reservation period expires, the ticket price may change, and you will need to confirm and pay for the booking. For more details or to reserve a flight without payment, you can contact 
+1-866-596-5078(OTA) for assistance.
+1-866-596-5078(OTA) for assistance.