Free SMTP for n8n using Cloudflare (no Sendgrid/Mailgun needed)

Tips & Tricks
1

Hey everyone :waving_hand:

I got tired of paying for transactional email services just to send a few notifications from n8n, so I built an open-source SMTP bridge that uses Cloudflare’s free Email Routing (200 emails/day).

The problem: n8n requires SMTP for email notifications, but most providers charge or have annoying setup processes.

The solution: A lightweight Node.js SMTP server that forwards emails to a Cloudflare Worker → Cloudflare Email Routing → recipient.

Features:

  • 100% free (Cloudflare free tier)

  • Rate limiting built-in (won’t exceed your quota)

  • Queue & automatic retries (SQLite-backed)

  • Attachments support

  • Health check endpoints for monitoring

n8n setup is simple:

yaml

services:
  n8n:
    environment:
      - N8N_EMAIL_MODE=smtp
      - N8N_SMTP_HOST=host.docker.internal
      - N8N_SMTP_PORT=2525
      - N8N_SMTP_SSL=false
      - [email protected]
    extra_hosts:
      - "host.docker.internal:host-gateway"

Requirements:

  • A domain on Cloudflare (free plan works)

  • Email Routing enabled

  • ~10 min setup

GitHub: https://github.com/MauricioPerera/smtp-bridge

Would love feedback from the community. PRs welcome!

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