At entry or exit, with direction of travel

Examples exist, particularly in North America, where passengers pay their fares to the driver on boarding the vehicle when traveling towards the city centre. The reverse process applies on outbound trips from the city centre, with payment then made as passengers alight from the vehicle.

This approach is most applicable to commuter routes from the suburbs to the city centre, rather than for other types of routes with many intermediate traffic generators coupled with a high turnover of short distance passengers. The presumption is made that the majority of passengers have a common destination area for the inbound journey, and that this locality is then the origin for most return journeys.

The advantage is that the number of fare transactions at each stop is limited, and hence the dwell time is minimal and schedule adherence is better. Further, this practice is compatible with a graduated fare structure in that the distance travelled by the passenger, and hence the applicable fare, is evident at the point of payment.
However the practice disadvantages any short-distance rider on the outer part of the route unless short-ride fares are also offered. In that case, the driver would need to check that the passenger had alighted where planned; that may be practicable where the numbers involved are few.