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I signed up for one (or two) Subject Test(s), and now I want to add another one (or two). What should I do?</p>
<p>If you want to add one or two Subject Tests other than a listening test, you do not have to contact us. The Subject Test books contain all the Subject Tests given on that date. If you want to take a listening test (offered in November only), you have to contact us by the late registration date (or, for students testing outside the United States, by the regular registration date).</p>
<p>You will be sent a bill for any additional test(s) you take.
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<p>^ From collegeboard.com</p>
<p>Is there a need to notify the proctor in doing so (adding a test)?</p>