At terminal or stop barrier

This practice is found in controlled-access environments, such as Bus Rapid Transit or Metro, where graduated fares apply. Validation at the barrier is required for confirmation that the correct fare has been paid or, alternatively, that the fare paid can be adjusted for the trip actually undertaken.

This latter feature is common for stored-value products, with the initial fare deducted at entry being that for the full remaining length of the route and any unused travel value then being rebated at exit.

At transport terminals and stops that have been designed to restrict access to and from the vehicles, some kind of control system is put in place. It may either be an automated barrier activated by the ticket media, or at a barrier for the manual inspection of travel documents.