Welcome to the NS Community query!

NS subscriptions are only valid when you travel by train. If you want a subscription for bus, tram or metro as well you can pick one up at the carrier concerned.

There ARE 1 or 2-all in local area seasons that are valid on all-around Utrecht. These cost a little more as bus/tram only and go by zones-not the distance in KMs. Also combi train+bus on some of the non-NS outer branch lines which were once (even in times of NS) organised to in fact keep trains running at the expense of cutting down parrallel buslines. As you likely ask for a specific trip, post details for a specific answer