Do I need a separate SIM for the WhatsApp Business API?

You do not always need a second SIM. Meta now documents a path where the Business app and Cloud API can share a number, and a migrate path that takes the number off the app.

I will not repeat the old line that one number can never sit in both places. That line is stale. The official pages are below.

One number, two official paths

A salon in Greater Kailash and a restaurant in Khan Market already printed one number. The fear is losing the chat history, or losing the digits on the card.

Meta’s migrate page says that to use an existing WhatsApp Messenger number with Cloud API you must first delete the Messenger account. For a Business app number you must either delete the account, or onboard through a partner who supports business app number onboarding. If you delete and then register for Cloud API, existing history is lost, and you cannot use that number with the Business app again unless you deregister from Cloud API.

Meta’s page on onboarding Business app users describes the other path, sometimes called coexistence. After a successful onboard, the shop can send high volumes through your app, still send one-to-one from the Business app, and WhatsApp keeps messaging history in sync. That page says the customer must use Business app version 2.24.17 or higher, and that numbers on both the app and Cloud API have a fixed throughput of 20 messages per second.

How to set up WhatsApp Business covers the free install. Wati versus AiSensy versus a direct build is the seat. This page is only the SIM.

A NexBuilt chatbot has a floor of Rs 15,000 on pricing. A second SIM is not inside that floor. If we need a new line, I name it before I start.

When you do not need a second SIM

You are staying on the free Business app. Then one SIM is enough. The cheapest thing that actually works often stops there.

You are moving to Cloud API through a partner who supports the onboard path above, and you want to keep tapping the app. Then the same digits can stay, if that onboard succeeds.

You are willing to delete the app account, accept the lost history, and live only on Cloud API. Then the same digits can move. Back up first. Meta’s migrate page says to back up.

When a second number is the honest path

The SIM on the board is also a family chat you will not share with a tool. Keep the family chat. Put the shop on a line you can move.

The onboard path fails, or no partner you trust supports it, and you will not delete the app history.

You want the personal WhatsApp and the shop API to be two lives. Two numbers. Two profiles. Hours on the shop one.

AiSensy’s pricing page, the day I opened it, also sold an Indian virtual number at Rs 2,000 plus GST a year, and said you do not need to maintain a SIM for that line. That is their product, not mine. I will not invent whether it fits your KYC.

What actually moves

The digits people already saved, if you keep or migrate them.

The history, if you use the onboard path and permit the sync. The history, if you delete, does not move. Meta says it is lost.

The listing. If the Google listing still shows a personal number, the API line will not get the tap. Fix the listing the same day.

Whether chatbots are useful still depends on the list, not on the SIM. A new number with a thin list is a new thin inbox.

Downsides of moving the number

People who only had the old personal chat will write into a dead thread.

A migrate you did not back up is a hole you cannot fill with a blog.

Coexistence has a throughput cap their docs name. If you later need more than that cap, you are in a different conversation.

I will not invent how many days a delete takes to clear. Meta’s migrate page says it may take up to 3 minutes for the disconnected number to become available. Trust that page over a vendor who needs a week for theatre.

Decide which of the three paths you are on

Stay on the app. Onboard and share. Or delete and move. Write that sentence before you buy a second SIM.

Then get in touch. Bring the number on the board and say which path you want. I will say the same SIM is enough, a second line is the job, or the free app still holds the week and the API can wait.