December 2, 1996

                              AN IMPORTANT REMINDER


To the Holders of the Credit Card Participation
  Certificates of Standard Credit Card Trust 1990-6

         On October 30, 1996 solicitation materials were mailed to you on behalf
of Citibank (South Dakota),  N.A., and Citibank (Nevada),  National  Association
(collectively,  the  "Banks"),  as  originators  of the  above-named  Trust (the
"Trust"),  relating to the proposed  amendment (the  "Amendment") of the Pooling
and  Servicing  Agreement  (the  "Agreement")  pursuant  to  which  Credit  Card
Participation  Certificates  of the Trust  (the  "Investor  Certificates")  were
issued.  According  to our  records,  your  consent  card  with  respect  to the
Amendment  has not yet been  received.  In order to be  effective,  your consent
needs to be received on or prior to December 18, 1996.

         The  Amendment  and the  reasons  why your  consent  is  requested  are
discussed  in the  solicitation  materials  previously  mailed  to you.  You are
encouraged to read those materials carefully and to contact the undersigned,  at
(718)  248-5163,  or Lisa Capuano,  at (718)  248-5827 if you have any questions
concerning  the Amendment.  If you need  additional  copies of the  solicitation
materials or need  assistance  in voting your  consent,  please call D.F. King &
Co., Inc. at (800) 669-5550.

         Regardless  of the size of your  holdings,  your  consent is  important
because  in order to  implement  the  Amendment  consents  from the  holders  of
Investor  Certificates  of the Trust  representing  not less than 66-2/3% of the
undivided  interest in the Trust must be received by December 18, 1996.  Failure
to complete and return a consent form will have the effect of a negative vote.

         Any Investor  Certificateholder  who gives its consent to the Amendment
may not revoke its consent.

         We urge you to complete,  sign, date and return the enclosed  duplicate
consent  form  today.  Your  interest  and  participation  in this  process  are
sincerely appreciated.

                                               Very truly yours,


                                               Vice President






                    IF YOU HAVE RECENTLY MAILED YOUR CONSENT,
              PLEASE ACCEPT OUR THANKS AND DISREGARD THIS REMINDER.