It depends on the testing center. Of my two tests so far, one center asked me for two IDs, the other only needed one.
You're safe as long as you follow the ID requirements on the back of the Notice to Schedule (NTS):
The same version of your name must appear on your application, this Notice to Schedule and on the identification you present at the testing center. You must present two forms of identification at the testing center, one of which must include a recent photograph and your signature and be on the list of primary forms of identification below. The other identification must include your signature. Neither form of identification may be expired.
Primary Forms of Identification:
Valid (not expired) government issued driver's license with photograph and signature. The license must be printed in
English to the extent required to compare the name with the one on the NTS and to confirm validity.
Valid (not expired) state identification card with a recent photograph and signature issued by one of the fifty U.S.
states or by a U.S. territory. (Candidates who do not drive may have an identification card issued by the agency which
also issues driver's licenses.)
Valid (not expired) government issued passport with a recent photograph and signature.
United States military identification card with a recent photograph and signature.
Secondary Forms of Identification:
Additional government issued identification from the above list.
Accountancy Board-issued identification.
Valid credit card (with signature).
Bank automated teller machine (ATM) card (with signature).
Valid bank debit card (with signature)
The following are UNACCEPTABLE forms of identification:
Draft classification card.
Social Security card.
Student identification card.
United States permanent residency card (green card).
FAR - Feb 2012 - 86
BEC - Apr 2012 - 85
AUD - Apr 2012 - 89
REG - May 2012 - 78
Review: CPAexcel + university review class + NinjaNotes (AUD®)