Difficulty:: beginner
Tools:: google-forms, google-sheets, google-apps-script, slack

Problem

A form writes a row and nobody sees it. The team either checks the sheet out of habit or finds out days later that someone was waiting on them.

Trigger

A form submission, through the spreadsheet's on form submit trigger.

Prerequisites

01A Google Form whose responses go to a spreadsheet.
02An incoming webhook URL from the chat tool.
03Permission to authorize a script on the account that owns the form.

Steps

01
Open the responses spreadsheet, then Extensions > Apps Script google-apps-script
02
Paste the script and save google-apps-script
03
Add SLACK_WEBHOOK_URL under Project Settings > Script properties slack
Script properties keep the webhook out of the code and out of version control.
04
Add the trigger google-apps-script
Triggers > Add trigger > function onFormSubmit > event source From spreadsheet > event type On form submit. Authorize when prompted.
05
Submit the form once as a test google-forms
Executions in the Apps Script sidebar shows the run and any error.

Payload · javascript

/**
 * Google Apps Script, bound to the form's responses spreadsheet.
 * Extensions > Apps Script, paste this, then add a trigger:
 * Triggers > Add trigger > onFormSubmit > From spreadsheet > On form submit.
 * Put the webhook in Project Settings > Script properties as SLACK_WEBHOOK_URL.
 */
function onFormSubmit(e) {
  const webhook = PropertiesService.getScriptProperties().getProperty('SLACK_WEBHOOK_URL');
  if (!webhook) throw new Error('Script property SLACK_WEBHOOK_URL is not set');

  const answers = e.namedValues;
  const lines = Object.keys(answers)
    .filter(function (question) { return String(answers[question]).trim() !== ''; })
    .map(function (question) { return '*' + question + '*: ' + answers[question]; });

  const body = {
    text: 'New form response',
    blocks: [{ type: 'section', text: { type: 'mrkdwn', text: lines.join('\n') } }]
  };

  UrlFetchApp.fetch(webhook, {
    method: 'post',
    contentType: 'application/json',
    payload: JSON.stringify(body),
    muteHttpExceptions: true
  });
}

Failure modes

!The trigger is attached to the form instead of the spreadsheet and e.namedValues is empty. It must be From spreadsheet.
!A long free text answer makes the message unreadable in chat. Post the questions that matter rather than all of them.
!The webhook is revoked and every run fails quietly. muteHttpExceptions keeps the row from being lost, so check Executions occasionally.
!Apps Script has daily quotas on UrlFetchApp. A form taking thousands of responses a day needs a different approach.

JSON-LD · HowTo

{
  "@context": "https://schema.org",
  "@type": "HowTo",
  "name": "Post every form response to a chat channel",
  "description": "An Apps Script trigger on the responses spreadsheet posts each new form submission to a chat channel as a readable message, so the people who act on it never open the sheet.",
  "url": "https://automationsanonymous.com/automations/post-every-form-response-to-chat",
  "tool": [
    {
      "@type": "HowToTool",
      "name": "google-forms",
      "url": "https://automationsanonymous.com/tools/google-forms"
    },
    {
      "@type": "HowToTool",
      "name": "google-sheets",
      "url": "https://automationsanonymous.com/tools/google-sheets"
    },
    {
      "@type": "HowToTool",
      "name": "google-apps-script",
      "url": "https://automationsanonymous.com/tools/google-apps-script"
    },
    {
      "@type": "HowToTool",
      "name": "slack",
      "url": "https://automationsanonymous.com/tools/slack"
    }
  ],
  "step": [
    {
      "@type": "HowToStep",
      "position": 1,
      "name": "Open the responses spreadsheet, then Extensions > Apps Script",
      "text": "Open the responses spreadsheet, then Extensions > Apps Script",
      "url": "https://automationsanonymous.com/tools/google-apps-script"
    },
    {
      "@type": "HowToStep",
      "position": 2,
      "name": "Paste the script and save",
      "text": "Paste the script and save",
      "url": "https://automationsanonymous.com/tools/google-apps-script"
    },
    {
      "@type": "HowToStep",
      "position": 3,
      "name": "Add SLACK_WEBHOOK_URL under Project Settings > Script properties",
      "text": "Script properties keep the webhook out of the code and out of version control.",
      "url": "https://automationsanonymous.com/tools/slack"
    },
    {
      "@type": "HowToStep",
      "position": 4,
      "name": "Add the trigger",
      "text": "Triggers > Add trigger > function onFormSubmit > event source From spreadsheet > event type On form submit. Authorize when prompted.",
      "url": "https://automationsanonymous.com/tools/google-apps-script"
    },
    {
      "@type": "HowToStep",
      "position": 5,
      "name": "Submit the form once as a test",
      "text": "Executions in the Apps Script sidebar shows the run and any error.",
      "url": "https://automationsanonymous.com/tools/google-forms"
    }
  ],
  "datePublished": "2026-09-05T16:53:37.448Z"
}