WhatsApp BSUIDs

📣 What You Need to Know About WhatsApp Usernames & BSUIDs

Dear Customer and Partner,

Meta is introducing WhatsApp Usernames, allowing users to interact with businesses without sharing their phone number.

As part of this change, Meta has introduced a new identifier called a Business-Scoped User ID (BSUID), which will be used to identify customers who choose not to share their phone number.

To help you navigate these updates without disruption, this guide outlines what this change means for your workflows, how our platform is preparing, and the steps you should take today.

What’s changing?

Historically, businesses have relied on a customer's phone number as their primary identifier. With Meta's gradual rollout of optional customer usernames, users who choose to adopt a username will have their phone numbers hidden by default in application webhooks. When a WhatsApp user adopts a username and chooses to hide their phone number, their phone number may no longer be available in future conversations.

Note: The same user receives a different BSUID for every business they message. Business A cannot use a BSUID to track a customer's interactions with Business B

Understanding the 30-Day Visibility Window

To support conversation continuity, Meta launched a native contact book infrastructure. This backend system automatically maps and stores phone numbers and BSUID pairs for active threads.

To minimize the risk of losing phone number visibility for existing customers, Meta will continue to include the customer's phone number in webhooks only if at least one of the following conditions is met:

• No Username Adopted: The customer has opted not to set up a public WhatsApp username (default behavior for users).
• Recent Outbound Interaction: You have sent a WhatsApp message or placed a WhatsApp call to the customer’s phone number within the last 30 days.
• Recent Inbound Interaction: You have received a message or call from the customer’s phone number within the last 30 days.
• Contact Book Match: The user's information has already been successfully captured in your Meta-hosted portfolio contact book since its rollout.

Note: Meta evaluates the 30-day interaction lookback per individual business phone number.

What CommBox is Doing on Our End

We have proactively updated our infrastructure to ensure a seamless transition as Meta scales this feature. CommBox is modifying its core messaging architecture to automatically capture, store, and map BSUIDs alongside your existing customer contact records. This ensures threads remain linked and automated backend logic can resolve customer identities even when Meta omits a phone number.

Immediate Actions for your Business:

1. Maintain Regular Outbound Cadences:
   Continue structured outbound messaging with active customers. Qualifying interactions reset Meta's 30-day lookback window, so regular communication directly safeguards your ongoing access to customer phone numbers.
   
   

2. Audit Automated Bot Flows & Routing:
   Specifically, customers need to review automated bot journeys, routing rules, or API webhooks that use the phone number as the absolute primary key to look up CRM records or authenticate users. Workflows should be adjusted to accept the BSUID as a valid fallback identifier. (Contact your CSM if you need help with the review process)
   
   

3. Prepare for Native Phone Number Requests:
   Meta is introducing a new Request Contact Info button for WhatsApp templates - including ready-to-use templates from Meta's template library. When a customer taps it, their phone number is shared instantly in the conversation thread, giving your team a compliant, consent-based path to re-establish phone number visibility when needed. CommBox will support adding this button when creating WhatsApp templates, with availability expected in August 2026.

WhatsApp Usernames and BSUIDs are currently being rolled out as a pilot in selected countries and are expected to become more broadly available over time. We will continue sharing updates as Meta provides additional guidance.

Questions?
Please contact your CommBox account manager or Customer Success Manager.