To activate your Citibank account online, visit Citi.com/activate. Once you're on the website, follow the step-by-step instructions provided to complete the activation process. Make sure to have your account information and any necessary identification documents ready. Citi.com activate offers a convenient and secure way to activate your Citibank account from the comfort of your own home. By following the simple steps outlined on the website, you can quickly and easily activate your account and gain access to all the benefits and features that Citibank has to offer.