ShapeShift charges a flat rate for all miner fees. Currently we do not have a dynamic fee system (nor do most coin networks allow for them). You may find that your actual miner fee is less than or, just as many times, more than the flat rate we charge and present on our About page. The miner fee we charge is the average, best fee for all coin networks, ensuring the funds are sent and confirmed in a timely manner. This is the miner fee structure we currently offer, no other line item fees are added.