<p>I've already registered for SAT II. However, I just realized that I would want to take a test for another subject. Is is possible for me to register for a new subject? Will it require me to pay extra?</p>
<p>You can take whatever tests you want, regardless of what you signed up for. However, if you are taking more tests than you signed up for a fee will billed to you. I believe less than $10.</p>
<p>I signed up for 2 tests (with a fee waiver) and took 3 at the testing room. I was billed 10 dollars by the College Board about a week after I got my scores. Good luck with your Subject Tests!</p>