WhatsApp users can now hide their phone number from businesses

WhatsApp is gradually rolling out optional usernames, and a person who uses one can message a business without the business seeing their phone number. For a customer, that is a privacy gain. For a business that has always treated the phone number as the way to tell customers apart, it is a change worth planning for.

What changed

Until now, a phone number identified the customer. Business chat tools used it to link conversations, match customer records and recognize people who came back. With a username, the number can stay private when someone contacts a business for the first time, unless they choose to share it. If the business already has the number from an earlier chat, it can keep seeing it. Usernames are optional, and a phone number is still required to create a WhatsApp account.

The new ID behind the scenes

To fill the gap, Meta introduced the Business-scoped User ID, or BSUID. It is a back-end identifier given to a WhatsApp user for their relationship with one particular business portfolio. Business-scoped means it is unique to that business, not a universal ID that follows the customer everywhere. Changing a username does not by itself change the BSUID, so past chats stay linked to the same person.

What it does not do

A BSUID tells a business who a WhatsApp user is in relation to it. It does not give the business a right to contact that person whenever it likes. WhatsApp's normal rules still apply, including conversation windows, template requirements and user preferences. Meta's current specifications also allow BSUIDs in many messaging situations, but some authentication template types still require a phone number.

What it looks like in practice

Take a customer named James who taps an Instagram ad and starts a WhatsApp chat. He has a username and has not shared his number. The business still needs to know his next message comes from the same James, keep his history, route him to a salesperson and later connect the chat to a customer record. The BSUID handles that. If James later shares his contact details, for example to finish an order or get a call, the business can use those too.

What to do

• Ask your chat or customer software provider whether it can recognize customers without a phone number.
• Check whether your customer records use the phone number as the only way to match people.
• Keep messaging rules in mind, since knowing who a customer is does not mean you can message them freely.