One WhatsApp number or two? Shopify notifications & support

By the Beacon Wave Studio team · Published October 1, 2026 · 9 min read

Should the number that sends Shopify order updates be the one your team answers on? Separate numbers, one shared number and Meta's Coexistence compared.

Every store that sets up WhatsApp notifications hits the same wall at the same step. The app asks for a phone number to register with Meta's Cloud API, you type the number printed on your business cards, and Meta tells you it is already in use by the WhatsApp Business app on your phone. Now you have a decision that nobody warned you about: give up the app on that number, buy a second number, or find out what the third option is.

This article is about that decision. It is not about templates or tokens; the Cloud API notifications guide covers those. It is about which number sends what, where a customer's reply ends up, and what each arrangement costs you in attention. It also explains Coexistence, the Meta feature that lets one number live in both places, and what it does and does not solve for a Shopify store.

Why the number cannot simply be in both

A WhatsApp phone number is registered to exactly one client. On your phone that client is the WhatsApp Business app. For automated Shopify notifications it is the Cloud API, which has no screen, no inbox and no phone; it sends and receives through web requests to your app. Historically, registering a number for the API deregistered it from the phone, which is why Beacon Messenger's setup notes say the number cannot be active in the app at the same time. The chat history stayed on the phone; the number stopped working there.

That constraint shaped how most small stores set things up: one number on a phone for humans, another in the API for robots. It works, and for many stores it is still the right answer. But it has a seam, and the seam is where customers reply.

Where a reply goes

A shipping update arrives on a customer's phone. They tap reply and type “can you send it to my work address instead?”. That reply travels back to whichever client owns the sending number. If the sender was an API-only number, the reply arrives as a webhook to the app that registered the number. Beacon Messenger receives those webhooks and reads the ones it needs, such as a YES or NO to a cash-on-delivery confirmation, which it records on the order. It does not run an inbox. A free-text reply about a work address is logged against the message and goes nowhere a human looks unless you give it somewhere to go.

This is the single most common surprise with API notifications, and it is not specific to any app. The Cloud API is a pipe, not a mailbox. Every store sending from an API-only number needs an answer to “who reads the replies?”, and the answers are: a helpdesk tool connected to the same number, a line in each template telling customers to contact the support number instead, or an arrangement where the sending number is also one a person answers.

Option A: two numbers, kept apart

The notifications number is API-only and the support number runs the WhatsApp Business app on a phone or on WhatsApp Web. The chat button on the storefront points at the support number, with the agents, hours and offline message described in the business-hours article. Each template ends with a line like “Questions? Message us on +44 20 …” or a button that opens the support chat.

Cheap. A second SIM or a virtual number costs a few dollars a month, and human replies on the Business app are not API messages, so they are not billed per message.
Clean separation of risk. If an automation misfires, it is a different number from the one your regulars chat to, and the quality rating of the support number is untouched.
The seam is visible to customers. Replying to a notification feels natural, and the one-line redirect in the template is the only thing standing between a customer and a message nobody sees. Some will miss it.
Two names in the customer's phone. The notification sender shows as one contact and support as another, which is fine when the display names make the roles obvious (“Oakfield Orders”, “Oakfield Support”) and confusing when they do not.

Option B: one number, moved entirely to the API

The business number is registered with the Cloud API and the phone app is given up. Notifications and human conversations both go through the API, and the humans work from a helpdesk or shared-inbox tool connected to the same WhatsApp Business Account. Replies to notifications land in the inbox automatically, because there is only one place for them to land.

One contact for the customer, and a reply always reaches a person. This is the arrangement larger stores end up in.
Every human message is now an API message. Since October 1, 2026 Meta charges for service messages beyond a monthly allowance, which the pricing-change article covers; a chatty support team can turn this into a line item.
You need the inbox tool, with its own subscription, and your staff need to learn it. The WhatsApp Business app's simplicity is the thing you give up.
Reversible, but not trivially. Moving a number back to the phone app means deregistering it from the API and re-verifying it, with templates and the delivery history of the API side left behind.

Option C: Coexistence, one number in both places

Meta now lets a number that is already on the WhatsApp Business app be onboarded to the Cloud API without leaving the app. Meta's developer documentation calls this onboarding WhatsApp Business app users and notes it is “sometimes referred to as Coexistence”. After onboarding, the business can send high volumes through the API while still messaging one-to-one from the app, and WhatsApp keeps the history between the two in sync. A notification sent by the API shows up in the phone's chat with that customer; the customer's reply shows up there too, and is also delivered to the API as a webhook.

For a small store this is close to the ideal: the robot sends from the number the humans already answer on, and replies land in the app they already use. There are conditions, all from Meta's documentation, and they are worth reading before you plan around it.

Onboarding happens through Meta's Embedded Signup flow run by a Solution Partner or Tech Provider, not by typing the number into a form yourself. The app on the phone must be version 2.24.17 or newer.
Throughput is fixed at 20 messages per second for a number used in both places. For a store's order notifications that is not a constraint; for a bulk campaign it might be.
The 24-hour customer service window applies to API messages only. Messages typed in the app are not subject to it, so a human can still reply to a week-old chat from the phone.
Partner documentation describes eligibility as depending on account tenure and messaging quality in the Business app, and warns that uninstalling the app disconnects the number from the API. Treat the number's phone as part of the infrastructure.
Business verification works differently for these accounts; several partners note that the standard flow is not available and point to partner-led verification instead. If a green tick or a high display-name tier matters to you, ask about this first.

Beacon Messenger connects to a number through its Cloud API credentials: the WhatsApp Business Account ID, the phone number ID and a permanent access token, as described in the Cloud API setup article. It does not run Embedded Signup itself. If you onboard a number with Coexistence through a partner, ask them whether you can generate your own system-user token for it; where you can, the number works in Beacon Messenger like any other, and the notifications it sends appear in the chat on your phone alongside the replies.

Choosing

Which number arrangement fits which store
Situation	Suggested arrangement	Why
A few orders a day, one or two people answering chats from a phone	Two numbers (A), with a redirect line in each template	Lowest cost and no new tools; the seam is manageable at this volume
Dozens of orders a day, support done from a desk	One number on the API (B) with an inbox tool	Replies to notifications must reach a person without relying on customers reading a footer
An established Business app number customers already know, team happy on the phone	Coexistence (C) if a partner offers it for your account	Keeps the number and the app, adds notifications, replies arrive where they always did
Cash-on-delivery confirmations are the main automation	Any; make sure the COD template's YES/NO replies are the only replies you depend on	Those replies are read by the app and recorded on the order regardless of arrangement

Whatever you choose, do these three things

Set the display name of the sending number to say what it is. “Oakfield Orders” tells a customer this contact sends updates; “Oakfield” on two contacts tells them nothing.
Put the human route inside the notification. A final line or a button pointing at the support number costs nothing and catches most of the replies that would otherwise vanish. Keep it factual so the template stays in the utility category.
Check the delivery log once a week for the first month. Beacon Messenger records every message with its Meta status and, for cash-on-delivery, the customer's reply; the delivery verification guide explains how to read it. If you see replies you did not expect, that is customers telling you where your seam is.

There is no arrangement that is right for every store, but there is one that is wrong for all of them: an API-only number with no plan for the replies. Decide where a customer's “can you change the address?” goes before the first notification is sent, and the rest follows. The plans page lists which automations each Beacon Messenger plan includes; the number they send from is yours to choose.

Frequently asked questions

Can I use my existing WhatsApp Business number for Shopify notifications?

Yes, in one of two ways. You can move the number to the Cloud API, which removes it from the phone app, and handle human chats through an inbox tool. Or, where a Meta partner offers it for your account, you can onboard the number with Coexistence, which lets it stay in the WhatsApp Business app while also sending through the API, with chat history kept in sync.

What happens when a customer replies to an automated WhatsApp order notification?

The reply goes to whichever client owns the sending number. For an API-only number that is a webhook to the app that registered it. Beacon Messenger reads cash-on-delivery YES/NO replies and records them on the order, but it has no inbox for free-text replies, so plan where those go: an inbox tool, a redirect line in the template, or a number that a person also answers.

What is WhatsApp Coexistence?

Meta's name for onboarding a phone number that is already on the WhatsApp Business app to the Cloud API without removing it from the app. Both keep working and messages are synchronised between them. It is set up through a Solution Partner or Tech Provider's Embedded Signup flow, requires app version 2.24.17 or newer, and fixes the number's throughput at 20 messages per second.

Is it cheaper to keep a separate number for support?

Usually, yes. Replies typed in the WhatsApp Business app are not API messages and are not billed per message, while human replies sent through the API count as service messages, which Meta began charging for beyond a monthly allowance on October 1, 2026. The trade-off is the seam between the two numbers, which a redirect line in each template mostly covers.