FASTag Must From Today, Pay Twice The Toll Fee If You Don't Have It FASTag Must From Today, Pay Twice The Toll Fee If You Don't Have It Those who don't install FASTag in their vehicles or have a tag that does not work will have to pay a fee equal to twice the fee for the category of the vehicle they are driving FASTag ensures highway toll payments are automatic and smooth, hence saving commute time New Delhi: The automatic toll plaza payment system FASTag will become mandatory from today midnight, the centre said on Sunday in a statement. Those who don't install FASTag in their vehicles or have a tag that does not work will have to pay twice the fee for the category of the vehicle they are driving.