Managing Several Clients' WhatsApp Numbers as an Agency

The first client you manage WhatsApp for is easy. You log in, send the messages, and report back on Friday. By the time you have eight clients, three team members and two numbers that someone linked to a personal laptop, the arrangement is a liability.

We've seen this pattern at small agencies more than once, and it's rarely about the tools. It's about who owns what, who can see what, and what happens when a client leaves. Sort those first, and the software choice gets much easier.

Decide who owns the number before you connect it

This is the single most expensive mistake. If you register a client's WhatsApp Business number under your agency's business account, you may find yourself holding something the client considers theirs. If the relationship ends badly, you have a problem, and they do too.

Our default advice is that the client's number belongs to the client's own business account, with your agency given access to operate it. Meta's current documentation explains how business accounts and access work, so check it rather than relying on our summary. And write the ownership position into the contract in plain language.

Keep every client in its own box

Contacts, conversations, templates and message history should never mix across clients. The obvious reason is privacy. The less obvious one is that a mistake in the wrong account, like a Diwali offer sent to the wrong client's list, is the kind of error that ends contracts.

Practical separation looks like this:

• One workspace or business account per client, never a shared contact list.
• A naming convention for numbers, templates and campaigns that includes the client's name.
• Separate API keys for each client, so you can revoke one without touching the rest.
• A rule that nobody tests campaigns on live client lists.

WA Getway is built around multiple numbers and per-business control, with an admin setting up each business and team members given access. That fits an agency's structure, but confirm the details in a demo for your own set-up before you promise anything to a client.

Access: your team will change, so plan for it

People leave agencies. A designer who had a client's WhatsApp login on their phone leaves in March, and nobody remembers to remove access until June. Treat access like office keys.

1. 1Give each team member their own login. Never share one password.
2. 2Give access only to the clients that person works on.
3. 3When someone leaves, remove their access the same day and rotate any API keys they had seen.
4. 4Keep a short list of who has access to what, reviewed each quarter.

Our post on keeping API keys safe goes deeper on the key side, which is where agencies are usually careless.

Consent and compliance are your problem too

When you send on a client's behalf, an unhappy recipient doesn't blame the agency. They report the client's number. If that number's quality drops, the client's business suffers and you're the one who explains why.

So make consent part of onboarding. For each client, ask where the contact list came from, how people agreed to receive messages, and how you'll record STOP requests. Our guides to WhatsApp opt-in and handling STOP requests are written so you can share them with clients directly.

If a client hands you a list bought from a vendor, decline politely. It's not worth the risk to their number or your reputation. Read why numbers get banned so you can explain it to them.

Billing and reporting without arguments

Clients ask the same question each month: what did I get for my money? Have a simple monthly report ready. Messages sent, delivered and replied to, per campaign, with notes on what you'd change.

On cost, plans with usage limits make it easier to price your service. If a gateway plan caps numbers and monthly messages, you can map each client to a plan and add your margin on top. Our guide to choosing plan limits covers how to estimate what a client really needs, and the Meta side has its own charges, so check Meta's current pricing before quoting.

Start small, and keep an exit

Don't migrate all clients at once. Take your most organised client first, run it for a month, write down what went wrong, and adjust. The client who can't tell you where their contact list came from should come last.

If you're an agency that wants a white-labelled set-up or a custom integration with your reporting tool, that's a conversation for our contact page. We'd rather scope it properly than promise features on a call.