How to Turn Slack Messages into Todoist Tasks with Zapier

zapier.com > Dashboard > Create Zap

Create a new Zap in Zapier

Log into zapier.com and click the orange 'Create Zap' button in the top-left sidebar. You'll land on the Zap editor — a two-panel view with a trigger block on the left and an empty action block below it. This is where you'll configure the full workflow. Give the Zap a name at the top (something like 'Slack Reaction → Todoist Task') so you can find it later.

1. 1Log in at zapier.com
2. 2Click 'Create Zap' in the left sidebar
3. 3Click the name field at the top and type 'Slack Reaction → Todoist Task'
4. 4Click the 'Trigger' block to begin setup

Zap Editor > Trigger > App & Event

Set Slack as the trigger app

In the trigger block, type 'Slack' into the search bar and select it from the results. You'll then be asked to choose a trigger event. Select 'New Reaction Added' — this fires every time any emoji reaction is added to any message in your workspace. This is the most reliable approach because it requires zero behavior change from your team; they just react to messages they want tracked.

1. 1Type 'Slack' in the app search field
2. 2Click Slack in the results
3. 3Click the 'Event' dropdown
4. 4Select 'New Reaction Added'
5. 5Click 'Continue'

Zap Editor > Trigger > Account

Connect your Slack account

Click 'Sign in to Slack'. A popup will open asking you to authorize Zapier to access your Slack workspace. You must be a workspace member to connect — Zapier needs read access to messages and reaction events. If your workspace uses Single Sign-On, the popup may redirect through your SSO provider first. After authorization, you'll be returned to the Zap editor with your account listed.

1. 1Click 'Sign in to Slack'
2. 2Select your workspace in the Slack authorization popup
3. 3Click 'Allow' to grant Zapier access
4. 4Confirm the connected account appears in the dropdown

Zap Editor > Trigger > Configure

Configure the trigger — pick your reaction and channel

You'll see two fields: 'Reaction' and 'Channel'. In the Reaction field, type the emoji name without colons — for example, type 'pushpin' for the 📌 emoji or 'white_check_mark' for ✅. Leave this blank if you want ALL reactions to create tasks (not recommended — that's too noisy). In the Channel field, choose a specific channel to watch or leave it set to 'Any Channel' if your team uses multiple channels for work. Click 'Continue' when done.

1. 1Type the emoji name (without colons) in the 'Reaction' field — e.g. 'pushpin'
2. 2Click the 'Channel' dropdown and choose a specific channel or leave as 'Any Channel'
3. 3Click 'Continue'

Zap Editor > Trigger > Test

Test the Slack trigger

Click 'Test trigger'. Zapier will pull the three most recent reactions matching your config from Slack. If no results appear, go into Slack right now, post a message in the configured channel, and add your chosen reaction to it — then come back and click 'Test trigger' again. You need real trigger data here because the field names from this test response are what you'll map to Todoist in the next steps.

1. 1Click 'Test trigger'
2. 2If no data loads, switch to Slack and react to a message with your chosen emoji
3. 3Return to Zapier and click 'Find new records'
4. 4Select one of the returned records to use as your test data
5. 5Click 'Continue with selected record'

Zap Editor > + > Filter by Zapier

Add a Filter step to avoid junk tasks

Click the '+' button between the trigger and the eventual action to add a Filter step. Set the filter condition to: 'Message Text — Contains — (any characters)' — meaning only proceed if the message has actual text content. This blocks reactions on image-only posts, link previews, and bot messages from creating empty Todoist tasks. Without this filter, blank tasks will appear in your Todoist inbox whenever someone reacts to a GIF or file upload.

1. 1Click the '+' icon between the trigger and action blocks
2. 2Select 'Filter by Zapier'
3. 3Set the left field to 'Message Text' from the Slack trigger data
4. 4Set the condition to 'Text contains'
5. 5Type a single space in the value field (to match any non-empty text)
6. 6Click 'Continue'

Zap Editor > Action > App & Event

Add Todoist as the action app

Click the action block and search for 'Todoist'. Select it, then choose 'Create Task' as the action event. This creates one new task per trigger — no batching, no deduplication needed for this use case. Click 'Continue' to move to account connection.

1. 1Click the Action block
2. 2Type 'Todoist' in the search field
3. 3Select Todoist from the results
4. 4Choose 'Create Task' from the Event dropdown
5. 5Click 'Continue'

Zap Editor > Action > Account

Connect your Todoist account

Click 'Sign in to Todoist'. A popup opens redirecting you to Todoist's OAuth page. Log in with the account that owns or has access to the project where tasks should land. Zapier uses OAuth 2.0 here — no API key required. After authorization, you'll return to the Zap editor with your Todoist account listed in the dropdown.

1. 1Click 'Sign in to Todoist'
2. 2Log into your Todoist account in the popup
3. 3Click 'Agree' to authorize Zapier
4. 4Confirm your Todoist email appears in the account dropdown

Zap Editor > Action > Configure

Map Slack data to Todoist task fields

This is the most important step. You'll see a form with Todoist task fields. For 'Task Content', click the field and insert the Slack 'Message Text' variable — optionally prefix it with something like 'Slack Task: ' for visual clarity in Todoist. For 'Project', choose a specific Todoist project from the dropdown or leave it as Inbox. For 'Description', insert the Slack 'Permalink' variable so every task links back to the original Slack message. Set 'Due Date' only if your team's convention is to always set deadlines — otherwise leave it blank.

1. 1Click the 'Task Content' field and select 'Message Text' from the Slack trigger data
2. 2Optionally prefix with static text like 'Slack: ' before the variable
3. 3Click the 'Project' dropdown and choose your target Todoist project
4. 4Click the 'Description' field and insert the 'Permalink' variable from Slack
5. 5Leave 'Due Date' blank unless your team always sets deadlines on flagged items
6. 6Click 'Continue'

Zap Editor > Action > Test

Test the action and verify the task in Todoist

Click 'Test action'. Zapier will fire against your connected Todoist account using the sample data from the trigger test. Switch to Todoist immediately after — open the project you mapped and confirm the task appeared with the correct message text and the Slack permalink in the description. If the task shows up blank or with wrong content, go back to step 9 and check the field mapping.

1. 1Click 'Test action'
2. 2Wait 5-10 seconds, then open Todoist in a new tab
3. 3Navigate to the project you configured
4. 4Confirm the task title matches the Slack message text
5. 5Click the task and verify the description contains the Slack permalink

Zap Editor > Publish

Turn on the Zap

Click 'Publish' in the top right of the Zap editor. The toggle will switch from gray to blue, confirming the Zap is live. From this point, every time someone adds your configured emoji reaction to a Slack message in the watched channel, a Todoist task will be created within 30 seconds. Share the emoji convention with your team — pin a message in the channel explaining which reaction triggers a task.

1. 1Click the 'Publish' button in the top right
2. 2Confirm the Zap status shows 'On' with a blue toggle
3. 3Go to Slack and post a message in the watched channel
4. 4React to it with your configured emoji
5. 5Check Todoist within 60 seconds to confirm the task was created

This Code by Zapier step extracts the @mention from the Slack message and appends it to the task title so the responsible person is visible at a glance in Todoist — without needing Todoist's assignee feature. Paste this into a 'Code by Zapier' step inserted between the Filter step and the Todoist action step. Set the input variable 'message' to the Slack Message Text field.

// Input variable: message (mapped from Slack Message Text)
const message = inputData.message || '';
// Extract the first @mention found in the message

// Input variable: message (mapped from Slack Message Text)
const message = inputData.message || '';

// Extract the first @mention found in the message
const mentionMatch = message.match(/@([a-zA-Z0-9._-]+)/);
const mention = mentionMatch ? mentionMatch[0] : null;

// Strip the @mention from the main task text to avoid redundancy
const cleanMessage = message.replace(/@([a-zA-Z0-9._-]+)/g, '').replace(/\s+/g, ' ').trim();

// Build the final task title
let taskTitle;
if (mention) {
  taskTitle = `${cleanMessage} [Owner: ${mention}]`;
} else {
  taskTitle = cleanMessage;
}

// Return both values for use in the Todoist action step
output = [
  {
    taskTitle: taskTitle,
    extractedMention: mention || 'unassigned'
  }
];