Difference between Transponder only entry Toll booths and Transponder only exit Toll Booths

Thread Starter


Joined Jun 7, 2012
I can't understand the difference between Transponder only entry Toll booths and Transponder only exit Toll booths. As far as I understand , Transponder entry only Toll booths check whether Transponder is operational or not and Transponder only exit Toll booths can do the transaction and deduct the Toll from the account associated with Transponder. But if the Transponder exit only toll booths can perform the payment, they can also do the detection, then why we need the Transponder only entry Toll booths?

Somebody please guide me.

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Joined Aug 21, 2008
"Seeing" the transponder as it enters and leaves the toll road/bridge allows the system to calculate the average speed and might be used to fine the transponder's account. If there are multiple entrances then knowing entrance used makes is possible to calculate the toll for that particular route.


Joined Oct 6, 2013
There are different types of toll roads. Where I live you pay by the mile on the turnpike. 50 cents will get you to the next exit in populated areas while say 50 miles will be a little more than $2.00. You get tagged as you enter and exit.

When I took a trip last fall I encountered the enter only types I believe. Every so often it there were transponders over the road and would charge another $1.90 I believe as you went under them and there was another transponder tagging the people getting on at the entrance. It didn't matter where you exited.