You will see the the procedure you need as a Citibank credit card Person to access their account through internet, in which they can make online payments, reach customer services number for further assistance.
Method of Access Account Online
Helpline Number-Make Payment by Phone
• The Citi credit card customer service phone number for payments is 800-950-
Credit Card Physically Payment Address
P.O. Box 9001037
Louisville KY, 40290-1037
Business address for Credit Card Payment
Pay your credit card bill at any Citibank Branch.