WalletHub, Financial Company
@WalletHub
The easiest way to reach Citi Diamond Preferred customer service is either online, thought the Citi Mobile app, or by calling (800) 950-5114. To speak to a live Citi customer service representative over the phone, say “customer service” any time during the call. Representatives are available 24 hours a day, 7 days a week. Alternatively, you can reach Citi Diamond Preferred customer service via mail, or by visiting a local Citibank branch for assistance.
Here’s how to reach Citi Diamond Preferred customer service:
- Online: Log in to your online account through Citi’s website or use the Citi Mobile App to live chat with a customer service representative.
- Phone Number: You can call customer service at (800) 950-5114.
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Mail: You can also contact customer service via mail. The address is:
Citibank Customer Service
P.O. Box 6500
Sioux Falls, SD 57117 - In person: Find a local Citibank branch.
If you call, an automated voice will ask for the last four digits of your Citi Diamond Preferred card, so make sure you have the card with you when you call. If you don’t have your card, be prepared to provide other verifying information such as your Social Security number (SSN). You will then hear a brief summary of your account. You can say “skip” at any time to bypass the account summary. At this point, you can ask to speak to customer service.
If you need to manage your account without speaking to a live representative, you’ll hear a list of options. You can either state the purpose of your call, such as “Payments,” or press the assigned number for that task. You will be routed to a new menu specific to your issue.

Citi® Diamond Preferred® Card
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