How-to

How to set up a Slack Workflow Builder flow for new members

When a new member joins your paid Slack community, the first tool most operators reach for is Workflow Builder — it’s free, built into every Slack workspace, and it can fire a welcome DM the moment someone joins. This guide walks through the exact setup, the personalisation tokens that work, what good welcome message copy looks like, and the three things Workflow Builder cannot do once your community scales past 100 paying members.

TL;DR

Create a new workflow, pick the “member joins channel” trigger, add a “send a message” step targeted at the joining member (not a channel), write a personalised welcome with a single action, and publish. Total time: 20–25 minutes. Free on every Slack plan. The three things Workflow Builder cannot do: send a conditional follow-up on day 3, key messages to goal data the member gave on day 0, or deliver a weekly operator scorecard. Those require a dedicated onboarding bot.

What you’ll build

A single Slack workflow that fires a direct message to every new member the moment they join your designated entry channel. The message greets them by name, tells them the one thing to do in the next 24 hours, and links to the channel where they should introduce themselves. Setup takes under 25 minutes and costs nothing. For a community under 100 members or one that has not yet automated anything, this is the highest-leverage step you can take this afternoon.

Step-by-step

Open Workflow Builder In your Slack workspace, click the lightning-bolt icon in the message composer (bottom-left of the text input area) and choose Open Workflow Builder. Alternatively: click your workspace name in the top-left → Tools & settings → Workflow Builder. On the Workflow Builder screen, click Create Workflow, then choose Build from scratch.
Choose the member-joined trigger Workflow Builder will ask you to select a trigger. Choose Member joins channel. When prompted, pick the channel that acts as your community entry point — commonly #general, #welcome, or #start-here. Every member who joins that channel from this point forward will trigger the workflow. If you want it to fire on workspace join (not channel join), you may need a Pro or Business+ Slack plan for the New member joins workspace trigger; channel join works on all plans.
Add a “Send a message” step Click Add Step and select Send a message. In the Send this message to field, select The person who joined (not a channel name). This routes the message as a direct message rather than a channel post. A direct message is harder to miss and feels more personal; a channel post in #welcome gets buried within minutes on an active workspace.
Write the message body Compose your welcome message. Use Slack’s variable tokens (click the curly-brace icon in the message editor) to personalise it. The tokens available in a member-joined workflow are shown in the table below. A solid welcome message has three parts: a greeting that uses their name, a single most-important action for today, and a link to where they should introduce themselves. Aim for 4–6 short sentences. Longer messages read as policy documents; shorter ones feel personal.
Publish the workflow Click Save on the step, then Publish on the workflow. The workflow goes live immediately. To test: have a colleague (or a test account) join the trigger channel. They should receive the DM within a few seconds. You will not receive anything — the message goes to the triggering member, not to you.

What you can personalise

Workflow Builder exposes a small set of built-in variable tokens for member-joined workflows. These are the ones worth using:

Token	What it inserts	Notes
@{{Person who joined}}	The member’s Slack display name, linked as a mention	Use in the greeting line. Most reliable token.
{{Workspace name}}	Your workspace’s display name	Useful if you manage multiple workspaces and template-share across them.
{{Channel}}	The name of the trigger channel	Less useful since it is always the same channel; include only if the message text needs to reference it explicitly.

There is no token for the member’s email address, their join date, or data they entered in a previous step. Each workflow step is stateless — the only data available is what the triggering event itself carries.

Three examples of welcome message copy

Minimal (fastest to write, still converts):

Hey @{{Person who joined}} — welcome to the community. Your first move: drop a line in #introduce-yourself and tell us what brought you here. Takes 60 seconds, and it’s how most members land their first useful conversation. Happy to help if you get stuck. — [Operator name]

With a goal-capture ask (harder to automate the answer, but worth asking):

Hey @{{Person who joined}} — glad you’re here. Two things from me: first, go post in #introduce-yourself so members know you’ve arrived. Second, reply here and tell me in a sentence what you most want to get out of the community. I read every reply and use it to point you toward the right threads. — [Operator name]

Longer, with channel map:

Hey @{{Person who joined}} — welcome. Here’s the fast start: (1) Post a two-sentence intro in #introduce-yourself. (2) Subscribe to the two channels most relevant to your work — the full list is pinned in #start-here. (3) Reply here with the one thing you want to learn or accomplish in your first month. I’ll follow up personally if I don’t hear from you by day 3. — [Operator name]

The third example is the closest to what a purpose-built onboarding bot automates: a goal-capture question on day 0, plus a stated intent to follow up if silent. Workflow Builder will send this message but cannot act on the reply or remember it for day 3.

What you cannot do with Workflow Builder alone

Send a conditional follow-up on day 3. Workflow Builder can schedule a message a fixed number of days after the trigger fires. What it cannot do is check what the member has done in the intervening days before deciding what to send. A member who posted twice gets the same day-3 message as a member who has been completely silent. The conditional check — “did this member complete their intro post?” — requires per-member state that Workflow Builder does not track.
Branch the day-3 message based on the member’s stated goal. If you asked “what brought you here?” in the day-0 DM and the member replied, Workflow Builder has no mechanism to read that reply and route the day-3 message accordingly. A member who said they joined for peer feedback needs a different nudge than a member who said they joined for the weekly live session. Sending one message to both segments means at least one segment gets a message that doesn’t match their situation.
Produce a weekly operator scorecard. After the workflow fires, Workflow Builder generates no reporting on member activation: how many members completed the intro post, how many replied to the goal-capture question, how many have been silent since the welcome DM, which specific members are at risk of churning. That data lives in Slack’s aggregate analytics (total active members) but not at the per-member resolution an operator needs to act on it. The question “which three members should I personally DM this week before they cancel?” is not answerable from Workflow Builder alone.

When to upgrade beyond Workflow Builder

Workflow Builder is the right answer at sub-100 members and for any community that has not yet automated the day-0 DM at all. The conditional day-3 nudge and the weekly operator scorecard become worth adding when you have 200 or more paying members and you start seeing a repeating pattern: members who join, engage for two days, and then go silent before posting. At that scale, a 20-minute Monday-morning DM session to the three most at-risk new members — armed with a scorecard that names who they are and why they’re at risk — moves the week-one activation rate measurably. That is what a purpose-built onboarding bot provides on top of what Workflow Builder delivers.

For a detailed, honest comparison of Workflow Builder versus a purpose-built bot at each community scale, see Slack Workflow Builder vs Foothold. For a map of all three automation tiers (Workflow Builder, Zapier, dedicated bot) and when each is the right layer to add, see Slack onboarding automation: three honest options.

Related: Slack Workflow Builder vs Foothold — detailed comparison of what each tool does well and where the ceiling is. Slack onboarding automation — three tiers — the full map from Workflow Builder to Zapier to purpose-built bot. What is a Slack onboarding bot? — definition of what the next layer adds.