Also called an application fee, this is the cost of signing up for a particular 529 plan. Depending on the program, you may not have to pay an enrollment fee at all, and those that do carry some type of fee typically charge fairly little – often in the neighborhood of $25 or $50. In some cases, the enrollment fee is lowered if you sign up online, are a resident of the state where the plan is administered, or are opening the plan for a new child.