Threshold Amount is the minimum amount that you need to maintain in your FASTag account, you can check the amount on this link To check your balance in tag account you may refer the details below: You receive SMS notifications from bank for each FASTag transaction You can log on to FASTag Customer Portal to check your account balance. To login please click https://fastag.kotak.com/ You can also call on contact center number; please call on 1860 2666 888 (local call charges applicable) / 1800 3006 9090 (Toll Free) (Car / Jeep / Van) Purple Color Tag for Vehicle class 4 (VC4). In case you have any other vehicle, please reach out to us the call center number mentioned on your tag and register your complaint or mail at nodal@ihmcl.com