They will charge your credit card for any and all tolls that occur during your rental of the vehicle.
They have one built in they will ask if you need it for an additional fee.
At your request they have a built in system to pay the tolls, for an additional fee. You'd be billed later once the tolls get processed. Check with them if all tolls in the States you plan to drive through are covered.
Thanks for the info guys. I guessed that there must be some kind of system because it looks like DFW is surrounded by toll roads.
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