To initiate a balance transfer with Citibank, locate the customer service number on the back of your Citibank credit card or visit the Citibank website for the appropriate contact information. Dial the customer service number and follow the prompts to speak with a representative. Inform them of your intention to initiate a balance transfer and provide the details of the account from which you wish to transfer the balance. The representative will guide you through the process, including any applicable fees and the timeframe for the transfer. Have your account information and desired transfer amount ready for a smooth transaction.