# How to onboard a new client in Slack

> Onboard a new ad client in Slack in one day: create the channels, invite the client, connect your tools, set each tool's client defaults and pin a welcome note.
- **Author**: Marxx
- **Published**: 2026-11-07
- **Category**: Agencies
- **URL**: https://marxx.ai/library-guides/how-to-onboard-a-new-client-in-slack

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On the first day with a new client, create its internal and shared channels, invite the client's people to the shared one only, point each ad tool at the right channels, and pin a welcome note that says who answers and when. The rest of onboarding (access, tracking, goals) runs alongside it from your normal checklist.

## Day one vs week one

| When | In Slack | Outside Slack |
|---|---|---|
| Day one | Create channels, invite the client, pin the welcome note | Contract signed, access requested |
| Days 2 to 3 | Connect tools, set client defaults, send test messages | Pixel and lead forms checked |
| Week one | First weekly update in the shared channel | Goals and budget agreed |

Our [client onboarding checklist for agencies](/templates/client-onboarding-checklist-for-agencies) covers the outside-Slack column.

## Step by step

1. **Create the internal channels** using your naming scheme, for example #client-sunpeak, #client-sunpeak-leads and #client-sunpeak-alerts. The [naming conventions template](/templates/slack-channel-naming-conventions-for-agencies) has the full set.
2. **Add your team** to the internal channels, and write the owner and backup in each description.
3. **Create the shared channel**, #ext-sunpeak. If the client has its own Slack, invite them through [Slack Connect](/glossary/slack-connect). If not, invite one or two people as guests.
4. **Connect your tools.** Add each tool's bot to the channels it should post in, then set the channel per client inside the tool.
5. **Set the client's defaults** in each tool: which messages go to Slack, and which channel each one uses.
6. **Send a test.** Create a test lead or trigger a test alert and check it lands in the right channel. For Meta lead forms, use [the Lead Ads Testing Tool](/guides/how-to-use-the-facebook-lead-ads-testing-tool).
7. **Pin the welcome note** in the shared channel.

We make Marxx. For a new client in Marxx, open Settings -> Integrations -> Slack -> Manage, pick that client's Default channel and choose what goes to Slack. Each client's settings are its own. Then add @Marxx to those channels. See [Marxx in Slack](/features/slack).

## The welcome note

Copy this into the shared channel and pin it.

```
Welcome to #ext-sunpeak.

This channel is for: weekly updates, approvals, questions.
From our side: Priya Shah (owner), Karan Mehta (backup).
We reply: 10am to 7pm, Monday to Saturday.
Weekly update: every Monday by noon.
Urgent (account blocked, offer change): tag @Priya.
```

## Worked example

Say Sunpeak Solar signs on Monday. By Monday evening, the four channels exist and the welcome note is pinned. On Tuesday, the buyer connects the lead tool and alerts tool, sends one test lead, and sees it in #client-sunpeak-leads within a minute. The first weekly update goes out the following Monday. Setup took about 90 minutes of one person's time, spread over two days.

## Common mistakes

- **Inviting the client before the channels are named and pinned.** First impressions set the tone.
- **Skipping the test message.** The first real lead lands in the wrong client's channel.
- **Adding the client's team to internal channels** to save time.
- **No welcome note.** The client does not know when you reply, and messages you at midnight.

## FAQ

### Should the client be in Slack at all?

Only if they want to be. Some clients prefer email or WhatsApp. Your internal channels work the same either way.

### How many people from the client should join?

Start with the decision maker and one day-to-day contact. Add more when they ask.

### When should tools be connected?

On day two or three, once access to the ad accounts is in place. A tool cannot post until it can read the account.

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- [More Agencies articles](https://marxx.ai/library-guides/category/agencies)
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