WhatsApp will allow users to exchange unique usernames instead of sharing phone numbers, a feature that will be rolled out globally to its three billion users over the next several months. The rollout begins on Monday, when users can reserve a username through the app, though using a username remains optional.

WhatsApp currently requires a phone number to create an account and to identify contacts, a requirement that has drawn scrutiny over data collection practices. Meta, the parent company, has been criticized for its handling of user information.

The username feature limits names to 35 characters and allows few restrictions, except that usernames for high‑profile officials and celebrities will not be made publicly available, reducing the likelihood of impersonation. Users can change or remove their usernames at any time. Phone numbers are still required to create an account and to discover contacts, and there is no public directory of usernames. The platform retains options to block or report unwanted messages, and the minimum age for using WhatsApp is 13. The upcoming UK social media ban for users under 16 does not apply to messaging apps.

Alice Newton‑Rex, WhatsApp’s head of product, said she had heard from users that they did not always want to share phone numbers, particularly in group chats, and that the feature would give users more control over how they appear on the app. Carisa Veliz, a professor at Oxford University and author of “Privacy is Power,” noted that while usernames improve privacy, WhatsApp is not a privacy‑friendly service because it collects metadata for advertising and is owned by Meta, a company with a poor privacy record. WhatsApp said the feature will help users keep their phone number private, but it emphasized that the app does not use the content of private chats for advertising, as messages are protected by end‑to‑end encryption.

The phased rollout will continue over the coming months, and WhatsApp has not specified when the feature will be fully implemented for all users.