Citigroup Inc. (NYSE: C) June 15, 2011

To Our Customers:

You may have recently read in the media about a compromise to Citi Account Online impacting credit card accounts in North America.

We wanted to share more specifics with you regarding the event. First, we want to confirm three things:

1. From the moment Citi discovered the breach we took immediate action to rectify the situation and protect any customers potentially at risk.
2. Customers are not liable for any fraud on the account and are 100% protected.
3. Every decision made throughout this process was in the best interest of our customers.

Updated Information on Recent Compromise to Citi Account Online For Our Customers

** Includes specific details, including dates and number of customers
impacted **

On May 10, a compromise to Citi Account Online that impacted roughly one percent of North America Citi-branded credit card accounts was discovered as part of routine monitoring and immediately rectified. While Citi Cards' Account Online system was compromised, the main cards processing system was not. Other Citi consumer banking online systems were not accessed or compromised.

Upon discovery, internal fraud alerts and enhanced monitoring were placed on all accounts deemed at risk. Simultaneously, rigorous analysis began to determine the precise accounts and type of information accessed. The majority of accounts impacted were identified within seven days of discovery. By May 24, we confirmed the full extent of information accessed on 360,069 accounts. An additional 14 accounts were confirmed subsequently. To determine the cardholder impact required analysis of millions of pieces of data.

The customers' account information (such as name, account number and contact information, including email address) was viewed. However, data that is critical to commit fraud was not compromised: the customers' social security number, date of birth, card expiration date and card security code (CVV).

While the investigation was underway, preparations began to notify customers and, as appropriate, replace affected customers' credit cards. As of May 24, we began the process of developing notification packages including customer letters and manufacturing replacement cards, as well as preparing our customer service teams. Notification letters were sent beginning June 3, the majority of which included reissued credit cards.

Citi has implemented enhanced procedures to prevent a recurrence of this type of event. We have also notified law enforcement and government officials. For the security of our customers, and because of the ongoing law enforcement investigation, we cannot disclose further details regarding how the data breach occurred.

Our customers are not liable for any unauthorized use of their accounts. We encourage our customers to review their account statements and to report any suspicious or unauthorized charges to us. Citi also offers free personalized identity theft solutions to assist our customers in taking appropriate steps if they believe they are a victim of identity theft.

Customers with additional questions can call the toll free number on the back of their card for help from Citi Customer Service. We continue to monitor customer service and communication channels and take every necessary action to ensure our customers are cared for.

DETAILS:
Total Accounts Impacted:

• A total of 360,083 North America Citi-branded credit card accounts were affected. Only accounts issued in the U.S. were impacted.
• 217,657 accounts were reissued credit cards along with a notification letter.
• Some accounts were not re-issued credit cards if the account is closed or has already received new credit cards as a result of other card replacement practices. These accounts continue to receive heightened monitoring for suspicious activity.
• State Numerical Account Breakdown included below.

State	Number of Accounts		State	Number of Accounts
AK	353		ND	608
AL	1,588		NE	1,063
AR	2,840		NH	1,116
AZ	6,600		NJ	8,791
CA	80,454		NM	2,246
CO	6,361		NV	2,946
CT	5,066		NY	25,312
DC	834		OH	5,547
DE	701		OK	5,208
FL	20,303		OR	3,839
GA	4,147		PA	8,490
HI	1,946		PR	105
IA	3,790		RI	827
ID	1,076		SC	1,657
IL	30,054		SD	886
IN	6,069		TN	2,753
KS	1,910		TX	44,134
KY	1,630		UT	1,955
LA	3,220		VA	5,337
MA	7,904		VI	79
MD	5,041		VT	509
ME	703		WA	6,511
MI	10,889		WI	7,838
MN	5,764		WV	525
MO	4,774		WY	485
MS	837		Other*	801
MT	839		Total	360,083
NC	4,822

*For example, includes addresses where the customer opened the account in the U.S. and may have a non-U.S. address currently on file.