Newsletter Automation

Complete newsletter management system with subscriber signup (double opt-in), automated welcome drip sequence, broadcast sender, and subscriber analytics. 4 production-ready n8n workflows with Google Sheets backend.

A complete newsletter management system built on n8n and Google Sheets. Handles subscriber signups with double opt-in, automated welcome drip emails, broadcast sending, and daily analytics reports.

Problem

Running a newsletter manually means juggling signup forms, confirmation emails, welcome sequences, and broadcast sends across multiple tools. Most newsletter platforms charge per subscriber, and you lose control of your data.

This system gives you a free, self-hosted newsletter pipeline using n8n and Google Sheets.

What It Does

1. Double Opt-In Signup — Webhook receives signups, validates email, sends confirmation link, stores in Sheets
2. Welcome Drip Sequence — Automatically sends Day 0 (welcome), Day 3 (tips), Day 7 (resources) emails
3. Broadcast Sender — API-triggered broadcast to all confirmed subscribers with unsubscribe links
4. Daily Analytics — Subscriber counts, growth metrics, confirmation rates, top sources

Included Workflows

#	File	Purpose
01	01-subscriber-signup.json	Webhook signup with validation, double opt-in, and Sheets storage
02	02-welcome-sequence.json	Scheduled drip emails at Day 0, 3, and 7
03	03-broadcast-sender.json	Webhook-triggered broadcast to all confirmed subscribers
04	04-subscriber-analytics.json	Daily metrics report email

Architecture

Signup Form (website)
    |
    v
Workflow 01: Subscriber Signup
    |
    +-> Validate email
    +-> Save to Google Sheets (status: pending)
    +-> Send confirmation email (double opt-in)
    +-> Return success response

User clicks confirmation link
    |
    v
Update Sheets (status: confirmed)

Scheduled (every 6 hours):
    |
    v
Workflow 02: Welcome Drip Sequence
    +-> Read confirmed subscribers
    +-> Check drip schedule (Day 0/3/7)
    +-> Send appropriate email
    +-> Update last_drip_day in Sheets

API Trigger:
    |
    v
Workflow 03: Broadcast Sender
    +-> Validate request + auth
    +-> Fetch confirmed subscribers
    +-> Send broadcast email to each
    +-> Include unsubscribe link

Daily Schedule:
    |
    v
Workflow 04: Subscriber Analytics
    +-> Read all subscribers
    +-> Calculate metrics (total, growth, rates)
    +-> Email report to admin

Required n8n Credentials

Credential Type	Used For	Placeholder in JSON
Google Sheets OAuth2	Subscriber storage	YOUR_GOOGLE_SHEETS_CREDENTIAL_ID
SMTP (Gmail or custom)	All emails (confirmation, drip, broadcast, reports)	YOUR_SMTP_CREDENTIAL_ID

Environment Variables

# Required
NEWSLETTER_ADMIN_EMAIL=[e-mail]
NEWSLETTER_BASE_URL=https://yourdomain.com
NEWSLETTER_SECRET=your-broadcast-api-secret

Configuration Placeholders

Placeholder	Description
YOUR_SUBSCRIBERS_SHEET_ID	Google Sheet ID for subscriber data
YOUR_GOOGLE_SHEETS_CREDENTIAL_ID	n8n Google Sheets credential ID
YOUR_SMTP_CREDENTIAL_ID	n8n SMTP credential ID
YOUR_NOTIFICATION_EMAIL	Fallback admin email (also set via NEWSLETTER_ADMIN_EMAIL env)
YOUR_DOMAIN	Fallback domain (also set via NEWSLETTER_BASE_URL env)

Google Sheets Schema (Subscribers)

Column	Type	Description
email	text	Primary key, subscriber email
name	text	Subscriber name
status	text	pending / confirmed / unsubscribed
source	text	Where they signed up (website, landing-page, etc.)
subscribed_at	datetime	Signup timestamp
confirmed	boolean	Whether email is confirmed
token	text	Confirmation token
last_drip_day	number	Last drip sent (0, 3, or 7)
last_drip_at	datetime	When last drip was sent

Quick Start

1. Prerequisites

• n8n v2.4+ (self-hosted)
• Google Sheets OAuth2 credentials
• SMTP email credentials

2. Create Subscriber Sheet

Create a Google Sheet with the columns above. Name the sheet tab "Subscribers".

3. Import Workflows

Import all 4 JSON files into n8n. Replace all YOUR_* placeholders.

4. Test Signup

curl -X POST https://your-n8n.com/webhook/newsletter/signup \
  -H "Content-Type: application/json" \
  -d '{"email": "[e-mail]", "name": "Test User", "source": "api-test"}'

5. Test Broadcast

curl -X POST https://your-n8n.com/webhook/newsletter/broadcast \
  -H "Content-Type: application/json" \
  -d '{
    "_secret": "your-newsletter-secret",
    "subject": "Test Broadcast",
    "content": "<p>This is a test broadcast.</p>"
  }'

Use Cases

1. Personal newsletters — Self-hosted alternative to Substack or ConvertKit
2. Business newsletters — Weekly updates to customers with zero per-subscriber cost
3. Product updates — Notify users about new features and releases
4. Community newsletters — Manage subscriber lists for communities or organizations
5. Content creators — Build an audience with automated drip sequences

Requirements

• n8n v2.4+ (self-hosted recommended)
• Google Sheets OAuth2 credentials
• SMTP email credentials (Gmail, SES, or custom)