There's going to be new machines installed soon which should accept cash. As Nicole and Jeff have said though you can currently use a credit card at the station to buy a ticket or use cash only on the train to get a ticket. The extra fee is $5 on top of the price of the ticket
Jeff is correct but keep in mind if you buy on the train its cash only and its a extra fee on the train.
If you have a credit card you can use the Quik Trak machine inside the station to buy a ticket. Otherwise you can buy it from the conductor on the train.
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