> For the complete documentation index, see [llms.txt](https://learn.doubletick.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://learn.doubletick.io/business-usernames-and-bsuid/whatsapp-usernames-and-bsuid-what-changes-for-your-business.md).
# WhatsApp Usernames and BSUID: What Changes for Your Business
Starting in 2026, WhatsApp is rolling out usernames in phases, letting users message businesses without sharing their phone number. When this happens, businesses will receive a new identifier called BSUID (Business-Scoped User ID) in place of that phone number.
This guide covers what's changing, how BSUID works, what you'll need to update, and just as importantly, what stays exactly the same.
***
#### **Why WhatsApp is introducing usernames**
Until now, starting a WhatsApp conversation meant sharing your phone number by default. A lot of users weren't comfortable with that, especially when they just wanted to ask a quick question or browse a product before committing to anything.
Usernames give users an alternative. Instead of sharing a phone number, they can message a business using a username, and keep their number private if they choose to.
This works in your favor too. Customers can now find and message you by searching for your business username directly, without needing to save or remember your phone number first.
**Businesses can adopt usernames too**
Just like users, businesses can also claim a username for their WhatsApp number, making it easier for customers to discover and message them without your number. If you haven't set yours up yet, see our guide on reserving a business username for your API number.
If your number carries verified business status with the green tick, that verification and your brand identity stay protected throughout this change. Nothing about this affects your verification status.
***
#### **What is BSUID**
When a customer messages you using a username instead of their phone number, WhatsApp sends you a BSUID (Business-Scoped User ID) in place of that phone number. Think of it as the new primary way to identify customers who've chosen to keep their number private.
A few things worth knowing about it:
* **Unique per business**. The same customer gets a different BSUID for every different business they message. This is by design; it protects the customer's privacy.
* **Generated automatically**. You don't need to request or set this up. It simply appears in your webhooks the moment a relevant customer messages you.
* **Scoped to your business portfolio**. BSUID is tied to your specific business, not shared or reused across unrelated businesses.
A BSUID looks like this: US.13491208655302741918. It starts with a two-letter country code, followed by a period, then a long alphanumeric string, up to 128 characters.
Important: always use the entire BSUID exactly as given, wherever you need it. Shortening or editing any part of it will cause the request to fail.
***
#### **What's actually changing**
**Before:** Phone number is the customer's identity.\
**After:** Phone number or BSUID is the customer's identity.
If a new customer starts a conversation using a username, you may only receive their BSUID, and not their phone number.
**Worth noting:** even after a customer adopts a username, their phone number can still show up in certain cases, for example if you've interacted with them recently, or they're already saved in your contact records.
**What this means practically:**
* Your CRM, chatbot flows, and any automations need to be able to handle a contact identified only by BSUID
* You may occasionally see conversations in your inbox with no phone number attached
***
#### **What's not changing**
The good news is that most of what you already do stays exactly the same:
* **Sending messages works the same way**. Templates, message types, and the overall process stay identical. You just use BSUID in place of a phone number when that's all you have.
* **Billing doesn't change**. The 24-hour conversation window and pricing logic work the same, regardless of whether the customer is identified by phone number or BSUID.
* **Your existing phone numbers are safe**. Any number you already have on file, from a past conversation, an ad click, an order, or your CRM, continues to work exactly as before.
* **Customers who haven't adopted a username are unaffected.** You'll keep receiving their phone number as usual.
***
#### **Important limitation: authentication messages**
**You cannot send OTP or verification code messages using a BSUID alone.**
Authentication templates, meaning one-tap, zero-tap, and copy-code formats, still require an actual phone number. If your business sends OTPs or verification codes, you'll need a plan to collect and store a customer's phone number, even if they first messaged you using a username.
***
#### **What you need to do to prepare**
* **Update your systems**. If your CRM, chatbot, or automation workflows assume every contact has a phone number, update that logic to also accept BSUID as a valid identifier.
* **Plan for OTPs**. If you send authentication messages, build a step into your conversation flow that asks for and stores the customer's phone number.
* **Check your connected tools**. Any third-party tool or integration you use alongside DoubleTick that relies on phone number as the only identifier may need an update.
* **Review your contact exports**. Make sure your exported contact data includes the BSUID field, not just phone numbers.
***
#### **In summary**
**What changes**: New customers may arrive identified by BSUID instead of phone number. Your systems need to accept BSUID as a valid identifier. OTP and authentication flows need a way to collect phone numbers.
**What stays the same:** Message sending, templates, and billing work exactly as before. Phone numbers you already have on record continue to work. The 24-hour conversation window and pricing logic are unchanged.
***
#### **Frequently asked questions**
**Can I search for or message a customer using just their username?**\
No. A username alone isn't enough to start a conversation. You need either the customer's phone number or their BSUID, and you only receive their BSUID after they've messaged you, tapped an ad, or scanned a QR code that starts the conversation.
**Does changing a username change the customer's BSUID?**\
No. The BSUID is tied to the customer's phone number, not their username. It only changes if the customer changes their actual phone number.
**Can I still message customers using their phone number?**\
Yes. As long as you have a customer's phone number on file, it remains a valid way to message them.
**What if a customer turns on username protection in the middle of an existing conversation?**\
Nothing changes for that conversation. Any phone number you'd already captured stays in your records and continues to work.
**Does this affect my messaging limits or conversation-based pricing?**\
No. Pricing and the 24-hour conversation window work exactly the same, whether a customer is identified by phone number or BSUID.
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