How to Assign Todoist Tasks from Slack Mentions with Zapier

zapier.com > Create Zap > Trigger > Search Apps

Create a new Zap and connect Slack

Go to zapier.com and click the orange 'Create Zap' button in the top left. The Zap editor opens with a blank trigger step. In the search box labeled 'Search for apps', type 'Slack' and select it from the dropdown. You'll be prompted to choose an event — this determines what fires the Zap.

1. 1Click the orange 'Create Zap' button in the left sidebar
2. 2Click the 'Trigger' block in the canvas
3. 3Type 'Slack' in the app search box
4. 4Select 'Slack' from the results list

Trigger > Event > New Mention

Set the trigger event to 'New Mention'

In the trigger event dropdown, scroll to find 'New Mention' and select it. This event fires any time your Zapier bot is @mentioned OR a specific user is @mentioned, depending on your configuration. Do not choose 'New Message Posted to Channel' — that fires on every message and you'll burn tasks fast. 'New Mention' scopes the trigger to only messages containing an @mention.

1. 1Click the 'Event' dropdown
2. 2Type 'mention' in the event search box
3. 3Select 'New Mention' from the list
4. 4Click 'Continue'

Trigger > Choose Account > Sign in to Slack

Connect your Slack account and authorize scopes

Click 'Sign in to Slack' and a popup window opens asking you to authorize Zapier. You must be logged into the correct Slack workspace in your browser before clicking. Zapier requests read access to messages and channel membership — both are required for this Zap. After clicking 'Allow', the popup closes and Zapier shows your workspace name with a green checkmark.

1. 1Click 'Sign in to Slack'
2. 2Select your workspace from the Slack authorization page
3. 3Click 'Allow' to grant Zapier the required permissions
4. 4Confirm the green checkmark appears next to your workspace name

Trigger > Configure > Channel

Configure the trigger to watch a specific channel

In the 'Configure' section, you'll see a 'Channel' dropdown. Click it and search for or select the specific channel you want this Zap to watch — for example, #client-acme. Leave the 'Trigger for' field set to 'Any mention' unless you want to restrict it to mentions of one specific user. Each Zap watches one channel. If you have three project channels, you'll build three separate Zaps or use Make's Router instead.

1. 1Click the 'Channel' dropdown
2. 2Type the channel name or scroll to find it
3. 3Select the target channel (e.g., #client-acme)
4. 4Leave 'Trigger for' as 'Any mention' unless restricting to one user
5. 5Click 'Continue'

Trigger > Test > Test trigger button

Test the Slack trigger with a real message

Click 'Test trigger' and Zapier pulls the most recent @mention from that channel. Go to Slack and post a test message in the target channel that includes an @mention — something like '@dana please review the mockups'. Wait 30 seconds, then click 'Test trigger' again. Zapier returns a sample record showing fields like 'Text', 'User', 'Channel', 'Timestamp', and 'Mentioned Users'. Check that 'Mentioned Users' contains the correct user ID — you'll map this to Todoist's assignee in a later step.

1. 1Post a test @mention message in your target Slack channel
2. 2Return to Zapier and click 'Test trigger'
3. 3Expand the returned sample record
4. 4Confirm 'Text', 'User', 'Mentioned Users', and 'Channel' fields are populated
5. 5Click 'Continue with selected record'

📬 New entry: {{1.name}}
Email: {{1.email}}
Details: {{1.description}}

Action > Search Apps > Todoist > Create Task

Add a Todoist action and connect your account

Click the '+' button below the trigger block to add an action. Search for 'Todoist' and select it. For the event, choose 'Create Task'. Click 'Sign in to Todoist' and a popup opens asking you to log in and authorize. Todoist's OAuth flow grants Zapier access to your projects and tasks. After authorizing, your Todoist account appears with a checkmark.

1. 1Click the '+' icon below the trigger block
2. 2Search for 'Todoist' in the app search field
3. 3Select 'Todoist' from the results
4. 4Choose 'Create Task' from the event dropdown
5. 5Click 'Sign in to Todoist' and complete the OAuth flow

Action (between steps) > Formatter by Zapier > Text > Extract Pattern

Add a Formatter step to extract the assignee's name

Before configuring Todoist fields, insert a Zapier Formatter step between the Slack trigger and Todoist action. Click the '+' between the two blocks and search for 'Formatter by Zapier'. Choose the 'Text' transform type, then select 'Extract Pattern'. Use the pattern '@(\w+)' to pull the first @mention out of the Slack message text. This gives you a readable username string you can use in the Todoist task content so it's human-legible — Todoist's free assignee field actually takes a user email, so this extracted name goes into the task title for context.

1. 1Click '+' between the Slack trigger and Todoist action
2. 2Search for 'Formatter by Zapier' and select it
3. 3Choose 'Text' as the transform type
4. 4Select 'Extract Pattern' from the Transform dropdown
5. 5Set Input to the Slack 'Text' field from step 5
6. 6Set Pattern to @(\w+) and click 'Continue'

📬 New entry: {{1.name}}
Email: {{1.email}}
Details: {{1.description}}

Action > Todoist > Configure > Field Mapping

Map Slack fields to Todoist task fields

In the Todoist 'Configure' section, you'll see fields for Content, Description, Project, Assignee, Due Date, and Priority. Map 'Content' to a combination of the Formatter output and the Slack message — something like 'Task for @[Formatter Output]: [Slack Text]'. Set 'Project' to the Todoist project that corresponds to this Slack channel. Leave 'Assignee' blank unless your team is on Todoist Business, which is the only plan that supports task assignment by email.

1. 1Click the 'Content' field and use the blue '+' icon to insert dynamic values
2. 2Insert the Formatter output (extracted username) followed by the Slack message Text
3. 3Click the 'Project' dropdown and select the matching Todoist project
4. 4Set 'Description' to the full Slack message Text for context
5. 5Optionally set 'Due Date' to today's date using Zapier's date formatting
6. 6Click 'Continue'

Action > Todoist > Configure > Priority

Set task priority based on channel or keywords

In the Priority field, you can either hardcode a value (1=normal, 4=urgent) or make it dynamic. To flag urgent tasks, add another Formatter step before Todoist that checks if the Slack message contains words like 'urgent' or 'ASAP', and outputs '4' or '1' accordingly. For a simpler setup, just hardcode Priority to '2' (high) for all tasks from project channels — this distinguishes these auto-created tasks from manually added ones.

1. 1Click the 'Priority' dropdown in the Todoist Configure section
2. 2Select '2' for high priority (or '4' for urgent)
3. 3Optionally insert a dynamic value from a Formatter step that returns priority based on keywords
4. 4Click 'Continue'

Action > Todoist > Test > Test action

Test the full Zap end to end

Click 'Test action' in the Todoist step. Zapier sends a real task to Todoist using the sample data from your Slack trigger test. Open Todoist and navigate to the project you selected — you should see the new task appear within 10 seconds. Check that the Content field shows the @mention and message text correctly, the project is right, and priority is set. If the task looks correct, click 'Publish Zap'.

1. 1Click 'Test action' in the Todoist step
2. 2Open Todoist in a new tab and navigate to your target project
3. 3Confirm the test task appears with correct content, project, and priority
4. 4Return to Zapier and click 'Publish Zap' if everything looks right

zapier.com > Zaps > [Your Zap] > Zap History

Turn on the Zap and verify live in Slack

After publishing, send a real @mention message in your target Slack channel — wait up to 2 minutes (Zapier's webhook latency is typically 30–90 seconds for Slack). Check Todoist for the new task. If it doesn't appear within 3 minutes, go to zapier.com > Zap History and look for any failed runs — the error detail there is almost always enough to diagnose the problem without contacting support.

1. 1Confirm the Zap toggle shows 'On' (green) on your Zaps dashboard
2. 2Post a real @mention message in the target Slack channel
3. 3Wait up to 2 minutes
4. 4Check Todoist for the new task
5. 5If missing, go to Zap History and inspect the most recent run for errors

This Code by Zapier step runs after the Slack trigger and before the Todoist action. It parses the Slack message to extract all @mentioned usernames, detects urgency keywords, and builds a clean task title and priority value. Paste this into a 'Code by Zapier' action step (choose 'Run JavaScript'), and map inputData.messageText to the Slack Text field and inputData.channelName to the Slack Channel Name field.

// Code by Zapier — Run JavaScript
// Inputs: inputData.messageText, inputData.channelName, inputData.senderName
const messageText = inputData.messageText || '';

// Code by Zapier — Run JavaScript
// Inputs: inputData.messageText, inputData.channelName, inputData.senderName

const messageText = inputData.messageText || '';
const channelName = inputData.channelName || 'unknown-channel';
const senderName = inputData.senderName || 'Someone';

// Extract all @mentions (Slack encoded format: <@UXXXXXXX> or plain @name)
const encodedMentions = messageText.match(/<@(\w+)>/g) || [];
const plainMentions = messageText.match(/@([\w.]+)/g) || [];

// Use plain mentions for display if available, fallback to encoded IDs
const displayMentions = plainMentions.length > 0
  ? plainMentions.join(', ')
  : encodedMentions.map(m => m.replace(/<@|>/g, '')).join(', ');

// Detect urgency keywords
const urgencyKeywords = ['urgent', 'asap', 'immediately', 'critical', 'eod', 'today'];
const isUrgent = urgencyKeywords.some(kw => messageText.toLowerCase().includes(kw));
const priority = isUrgent ? 4 : 2;

// Strip Slack encoding from message for clean description
const cleanMessage = messageText.replace(/<@\w+>/g, (match) => {
  return match.replace(/<@|>/g, '@');
});

// Build task title
const taskTitle = displayMentions
  ? `Task for ${displayMentions}: ${cleanMessage.substring(0, 100)}`
  : `Task from ${senderName}: ${cleanMessage.substring(0, 100)}`;

// Build description with Slack context
const description = `From: #${channelName}\nAssigned by: ${senderName}\n\nFull message:\n${cleanMessage}`;

return {
  taskTitle: taskTitle,
  description: description,
  priority: priority,
  isUrgent: isUrgent,
  mentionedUsers: displayMentions
};