How to Send Gmail Digest Summaries to Slack with n8n

n8n Canvas > + Add first step > Schedule Trigger

Create a new n8n workflow with a Schedule trigger

Open your n8n instance and click the '+ New Workflow' button in the top right. On the blank canvas, click the '+ Add first step' placeholder node. In the node picker panel that slides in from the right, type 'Schedule' and select the 'Schedule Trigger' node. This will fire the workflow at whatever cadence you configure — daily at 9am or weekly on Monday morning are the most useful for email digests.

1. 1Click '+ New Workflow' in the top right of the n8n dashboard
2. 2Click the '+ Add first step' node on the empty canvas
3. 3Type 'Schedule' in the search box of the node picker
4. 4Select 'Schedule Trigger' from the results
5. 5In the node settings panel, set 'Trigger Interval' to 'Days' and 'Days Between Triggers' to 1, with 'Trigger at Hour' set to 9

n8n Canvas > + Node > Gmail > Credential > Create New > OAuth2

Connect your Gmail account to n8n

Click the '+' button after the Schedule Trigger node to add the next step. Search for 'Gmail' in the node picker and select the Gmail node. In the node settings, click the 'Credential for Gmail API' dropdown and select 'Create New Credential'. n8n will ask you to choose between OAuth2 and a Service Account — use OAuth2 for a personal or shared team Gmail account. You'll be redirected to Google's consent screen to authorize access.

1. 1Click the '+' connector on the right side of the Schedule Trigger node
2. 2Search 'Gmail' in the node picker and click the Gmail node
3. 3In the node panel, click the 'Credential for Gmail API' dropdown
4. 4Click 'Create New Credential'
5. 5Select 'OAuth2' as the credential type and click 'Sign in with Google'
6. 6Complete Google's OAuth consent flow and grant the requested Gmail scopes

Gmail Node > Resource: Message > Operation: Get Many > Filters > Query

Configure Gmail to fetch emails from the last 24 hours

With the Gmail node open, set 'Operation' to 'Get Many' and 'Resource' to 'Message'. In the 'Filters' section, you'll use Gmail's search query syntax in the 'Query' field — this is the most important configuration in the entire workflow. The query controls exactly which emails get pulled. Set the 'Limit' field to 50 to avoid pulling hundreds of messages on busy days.

1. 1Set 'Resource' to 'Message'
2. 2Set 'Operation' to 'Get Many'
3. 3In the 'Query' field, enter your filter — see examples below
4. 4Set 'Limit' to 50
5. 5Toggle 'Return All' to OFF

Gmail Node > Filters > Query field

Build Gmail query filters for your team's use case

The Gmail query field accepts the same search operators as the Gmail web UI. Pick the query pattern that matches your team's need. For emails from a specific client domain, use 'from:(@acmecorp.com) newer_than:1d is:unread'. For labeled messages, use 'label:priority newer_than:1d'. For all unread messages, use 'is:unread newer_than:1d'. You can combine multiple operators with AND — Gmail treats space-separated terms as AND by default.

1. 1Decide which filter pattern fits your team: domain, label, or unread
2. 2For domain-based: type 'from:(@yourdomain.com) newer_than:1d is:unread'
3. 3For label-based: type 'label:your-label-name newer_than:1d'
4. 4Click 'Test step' to verify the query returns expected emails
5. 5Adjust the query if the result set is too large or too narrow

n8n Canvas > + Node > Code > JavaScript mode

Add a Code node to format the email data into a digest

Click '+' after the Gmail node and add a 'Code' node. This is where you transform the raw email array into a clean, readable Slack message. The Code node runs JavaScript and has access to all Gmail output via the $input.all() method. You'll loop over each email item, extract subject, sender, snippet, and date, then build a single formatted string that Slack can render with its Block Kit or simple mrkdwn syntax.

1. 1Click '+' after the Gmail node
2. 2Search for 'Code' in the node picker and select the Code node
3. 3Make sure 'Language' is set to 'JavaScript'
4. 4Set 'Mode' to 'Run Once for All Items'
5. 5Paste the digest-formatting code from the Pro Tip section below

This Code node runs once for all Gmail items, builds a formatted Slack mrkdwn digest string with direct Gmail links, handles missing fields safely, and deduplicates by threadId so reply chains only appear once. Paste this into the Code node in Step 5, with 'Mode' set to 'Run Once for All Items'.

// n8n Code Node — Run Once for All Items
// Transforms Gmail message array into a single Slack mrkdwn digest string
const items = $input.all();

// n8n Code Node — Run Once for All Items
// Transforms Gmail message array into a single Slack mrkdwn digest string

const items = $input.all();
const now = new Date();
const dateLabel = now.toLocaleDateString('en-US', { weekday: 'long', month: 'short', day: 'numeric', year: 'numeric' });

// Deduplicate by threadId — only show the most recent message per thread
const seenThreads = new Set();
const dedupedItems = [];

for (const item of items) {
  const threadId = item.json.threadId ?? item.json.id;
  if (!seenThreads.has(threadId)) {
    seenThreads.add(threadId);
    dedupedItems.push(item);
  }
}

// Sort by date descending (newest first)
dedupedItems.sort((a, b) => {
  const dateA = new Date(a.json.date ?? 0).getTime();
  const dateB = new Date(b.json.date ?? 0).getTime();
  return dateB - dateA;
});

if (dedupedItems.length === 0) {
  return [{ json: { digestText: ':white_check_mark: No priority emails in the last 24 hours.', emailCount: 0 } }];
}

// Build the header
let digestLines = [];
digestLines.push(`*📧 Email Digest — ${dateLabel}*`);
digestLines.push(`_${dedupedItems.length} email${dedupedItems.length > 1 ? 's' : ''} from the last 24 hours_`);
digestLines.push('');

// Build one block per email
dedupedItems.forEach((item, index) => {
  const subject = item.json.subject ?? '(no subject)';
  const from = item.json.from ?? '(unknown sender)';
  const snippet = (item.json.snippet ?? '').substring(0, 120);
  const threadId = item.json.threadId ?? item.json.id ?? '';
  const rawDate = item.json.date ? new Date(item.json.date) : null;
  const timeLabel = rawDate
    ? rawDate.toLocaleTimeString('en-US', { hour: 'numeric', minute: '2-digit' })
    : 'unknown time';

  const gmailLink = threadId
    ? `https://mail.google.com/mail/u/0/#inbox/${threadId}`
    : 'https://mail.google.com';

  digestLines.push(`*${index + 1}. ${subject}*`);
  digestLines.push(`👤 ${from} · ${timeLabel}`);
  digestLines.push(`> ${snippet}${snippet.length === 120 ? '...' : ''}`);
  digestLines.push(`🔗 <${gmailLink}|Open in Gmail>`);
  digestLines.push('');
});

const digestText = digestLines.join('\n').trim();

return [{ json: { digestText, emailCount: dedupedItems.length } }];

n8n Canvas > + Node > IF > Condition Builder

Handle the empty-inbox case gracefully

If no emails match your Gmail query, the Gmail node returns zero items and the Code node will produce an empty digest. Add an IF node between the Gmail node and the Code node to check the item count. If zero emails came back, route to a separate Slack node that posts 'No priority emails in the last 24 hours — inbox clear.' This prevents the digest from posting a blank or confusing message to Slack.

1. 1Click '+' after the Gmail node to insert a node before the Code node
2. 2Search for 'IF' and select the IF node
3. 3In the condition builder, set 'Value 1' to the expression: {{ $input.all().length }}
4. 4Set the operator to 'Greater Than' and 'Value 2' to 0
5. 5Connect the TRUE branch to the Code node and the FALSE branch to a new Slack node

n8n Canvas > + Node > Slack > Credential > Create New > Bot Token

Connect your Slack account and configure the Slack node

Click '+' after the Code node and add a Slack node. Click 'Credential for Slack API' and select 'Create New Credential'. You'll need a Slack Bot Token (starts with xoxb-) from a Slack App you create at api.slack.com/apps. The bot needs the chat:write scope to post messages. Set 'Operation' to 'Post Message' and choose the Resource as 'Message'.

1. 1Click '+' after the Code node
2. 2Search 'Slack' and select the Slack node
3. 3Click 'Credential for Slack API' and select 'Create New Credential'
4. 4Paste your Slack Bot Token (xoxb-...) into the 'Access Token' field
5. 5Click 'Save' and confirm the green checkmark appears
6. 6Set 'Operation' to 'Post Message' and 'Resource' to 'Message'

Slack Node > Channel > Text > Appearance

Configure the Slack message with the digest content

In the Slack node, set 'Channel' to your target channel name or ID — using the channel ID (starts with C0...) is more reliable than the name since channel names can change. In the 'Text' field, use the expression editor to reference the Code node output: {{ $node['Code'].json.digestText }}. Enable 'As User' if you want the message to appear from the bot's name. Set 'Username' to something like 'Email Digest' and optionally add a mail emoji as the icon.

1. 1In the 'Channel' field, enter your Slack channel ID (e.g. C04ABCDE123)
2. 2Click the expression toggle on the 'Text' field (the lightning bolt icon)
3. 3Type or paste: {{ $node['Code'].json.digestText }}
4. 4Optionally set 'Username' to 'Email Digest' under 'Other Options'
5. 5Optionally set 'Icon Emoji' to ':email:'

IF Node > FALSE branch > + Node > Slack

Wire the empty-inbox Slack node for the FALSE branch

Go back to the IF node's FALSE output branch and connect it to a second Slack node. Configure this node with the same channel and credentials. In the 'Text' field, type a static message: ':white_check_mark: No priority emails in the last 24 hours.' This gives the team a positive signal that the digest ran — not just silence — which matters for trust in the automation.

1. 1Click the FALSE output circle on the IF node
2. 2Select the Slack node from the picker
3. 3Use the same Slack credential as step 7
4. 4Set the same channel ID
5. 5In 'Text', enter ':white_check_mark: No priority emails in the last 24 hours.'

n8n Workflow Editor > Save > Active Toggle > Executions Panel

Activate the workflow and verify the first scheduled run

Click 'Save' in the top right, then toggle the workflow from 'Inactive' to 'Active' using the toggle in the top bar. The workflow will now run at your configured schedule. To verify without waiting, click the three-dot menu next to the workflow name and select 'Execute Workflow' to trigger a manual test run. Check the Slack channel for the digest message and review the execution log in the n8n 'Executions' panel for any errors.

1. 1Click the 'Save' button in the top right of the editor
2. 2Click the toggle switch in the top bar to set the workflow to 'Active'
3. 3Click the three-dot menu next to the workflow name
4. 4Select 'Execute Workflow' for an immediate test run
5. 5Open the 'Executions' tab in the left sidebar to confirm a green success status

Workflow Editor > Settings (gear icon) > Error Workflow

Set up error notifications so silent failures don't go unnoticed

Scheduled workflows fail silently unless you set up an error handler. In n8n, go to the workflow settings by clicking the gear icon in the top bar. Under 'Error Workflow', select an existing error-handler workflow or create a simple one that posts a Slack message to a #alerts channel when an execution fails. Without this, a Gmail API credential expiry or Slack rate limit can cause days of missed digests before anyone notices.

1. 1Click the gear icon in the top right of the workflow editor
2. 2Scroll to the 'Error Workflow' section
3. 3Click 'Select Workflow' and choose an existing error handler, or click 'Create New'
4. 4In the error handler workflow, add a Slack node that posts to #alerts with the message: 'Email Digest workflow failed: {{ $json.error.message }}'
5. 5Save both workflows