As AP sign up deadlines hurdle around the corner, it is important to remember to sign up for all of your tests before Nov. 4th. Each test costs $96 to take, however signing up late could result in a $225 late fee. To sign up, reference the step by step instructions that your teachers should have handed out to you. From there, it will direct you to a link that will ask you to register for each exam for each class under your AP portal.