n8n Lead Filter Workflow: Spam/Pitches to Google Sheets

Turn contact-form submissions into real leads—automatically filter spam and pitches

This n8n Lead Filter Workflow captures website form submissions, validates and enriches them with Twilio Lookup and OpenAI, then files each entry into the right Google Sheets tab—Leads, Pitches, or Spam—while notifying you via Gmail (and optional Twilio SMS).

What this workflow does

• Triggers when a website form posts to a webhook, when an n8n built-in form is submitted, on a scheduled Monday 7am run, or via a one-time manual setup.
• Normalizes inputs (name, email, phone, message, etc.) and checks the recent “Leads” tab to detect repeat contacts.
• Runs rule-based spam checks including honeypot detection, too-fast submissions, excessive links, disposable emails, and missing contact details.
• Validates phone numbers using the Twilio Lookup API when applicable.
• Reads your Services definitions from Google Sheets and sends the submission plus validation results to OpenAI to classify it as: customer/vendor pitch/job seeker/spam/unclear, including urgency, summary, and a suggested reply.
• Appends the classified result into the proper Google Sheets tab: Leads, Pitches, or Spam.
• Notifies you by email via Gmail for leads (and optionally sends you Twilio SMS), with an optional acknowledgment email to the customer.
• Sends a weekly Gmail summary every Monday at 7am based on the last 7 days across the three tabs.

Use cases

• Stop spam and low-quality pitches from polluting your CRM spreadsheets.
• Auto-route inbound messages into “Leads” vs “Pitches” vs “Spam” with AI-assisted classification.
• Enrich submissions with Twilio phone validation and a suggested response to speed up follow-up.

Technical details

• Integrations/nodes: if, set, code, gmail, switch, twilio
• Data storage: Google Sheets (“Leads” tab plus destinations for Pitches and Spam)
• AI + enrichment: Twilio Lookup API + OpenAI classification using your Google Sheets “Services” definitions