Citibank Customer Service

Online Technical Assistance
1-800-347-4934
TTY: 1-800-325-2865

CitiBusiness and Professional Cards
Online Technical Assistance
1-866-422-3091
TTY: 1-800-325-2865

Lost or Stolen Credit Cards or General Account Information
1-800-950-5114
TTY: 1-800-325-2865

Outside the U.S. -- Call Collect
1-605-335-2222

Internet Security Specialists
1-888-285-9696
TTY: 1-800-325-2865
   
Costco Credit Card Application Status
1-877-343-4118
TTY: 1-866-210-0617

Credit Card Application Status
1-888-201-4523
TTY: 1-800-325-2865

Servicio al cliente español
1-800-947-9100
TTY: 1-800-325-2865

https://online.citi.com