Where to Find Free Email Services for Transactional Emails: The Complete Developer Guide

The free-for-dev repository maintains a curated "Email" section listing dozens of free email services for transactional emails, including providers like Resend, MailerSend, and Brevo that offer between 100 and 15,000 free emails per month.

Finding reliable free email services for transactional emails is essential for developers testing authentication flows, notifications, and automated messaging without incurring costs. The ripienaar/free-for-dev repository serves as the definitive community-curated resource, cataloging free-tier limits and integration details for transactional email providers in its central README.md file. This guide walks you through the repository's Email section and demonstrates how to integrate the most popular free services into your applications.

Locating Free Transactional Email Providers in free-for-dev

The complete inventory of free email services resides in the Email section of README.md at the root of the repository. This section organizes providers by capability—SMTP relay, REST API, sandbox testing, and disposable inboxes—while explicitly noting monthly sending limits, domain restrictions, and webhook support.

You can locate the complete list in the README under the "Email" heading. The file uses a single Markdown structure where each service entry appears as a bullet point linking directly to the provider's website and noting specific free-tier limits.

Top Free Transactional Email Services and Quotas

The repository lists the following production-ready services specifically suited for transactional email workflows:

• Resend – 3,000 emails/month (100/day limit), 1 custom domain, modern REST API
• MailerSend – 3,000 emails/month, dedicated transactional API with detailed analytics
• Brevo (formerly Sendinblue) – 9,000 emails/month (~300/day), SMTP and API access with contact management
• AhaSend – 1,000 emails/month, unlimited domains, webhooks, and routing rules
• Sendpulse – 15,000 emails/month, 500 subscriber limit, multi-channel (email, push, SMS)
• Postmark – 100 emails/month, high-deliverability API with detailed event logs
• MailChannels – 3,000 emails/month, SMTP and REST API suitable for high-volume bulk

For development and testing, the repository also highlights EtherealMail (unlimited fake SMTP where messages are captured but never delivered) and Mailtrap (3,500 emails/month sandbox environment).

Integrating Free Transactional Email Services: Code Examples

The following examples demonstrate how to send transactional emails using three distinct approaches from the free-for-dev list: a fake SMTP server for local development, a production REST API via cURL, and a modern JavaScript SDK.

EtherealMail: Unlimited Fake SMTP for Development

EtherealMail provides an unlimited fake SMTP service ideal for testing Nodemailer or other SMTP clients without risking real delivery. Messages are accepted by the server but remain viewable only through the Ethereal web interface.

# Python example using aiosmtplib

import aiosmtplib
import email.message

msg = email.message.EmailMessage()
msg["From"] = "[email protected]"
msg["To"] = "[email protected]"
msg["Subject"] = "Welcome to MyApp"
msg.set_content("Your account has been created successfully.")

# Replace with credentials from EtherealMail dashboard

await aiosmtplib.send(
    msg,
    hostname="smtp.ethereal.email",
    port=587,
    start_tls=True,
    username="your_ethereal_user",
    password="your_ethereal_pass",
)

MailerSend: Production-Ready Transactional API

MailerSend offers a dedicated transactional email API with a free tier of 3,000 emails per month. The service provides detailed delivery statistics and supports both SMTP and REST endpoints.

# Send via MailerSend REST API using curl

curl -X POST "https://api.mailersend.com/v1/email" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
        "from": {"email":"[email protected]","name":"MyApp"},
        "to": [{"email":"[email protected]","name":"John"}],
        "subject":"Welcome!",
        "html_content":"<p>Thanks for signing up.</p>"
      }'

Resend: Modern Developer-Focused Email API

Resend provides a clean, modern API specifically designed for developers sending transactional emails. The free tier includes 3,000 emails per month with a daily limit of 100 messages and support for one custom domain.

// Node.js example using the Resend SDK
// Install: npm i @resend/resend
import { Resend } from "@resend/resend";

const resend = new Resend("re_XXXXXXXXXXXXXXXXXXXXXXXX");

await resend.emails.send({
  from: "Acme <[email protected]>",
  to: "[email protected]",
  subject: "Your receipt",
  html: "<p>Here is your receipt for order #1234.</p>",
});

Key Files in the free-for-dev Repository

Understanding the repository structure helps you navigate the curated lists efficiently. The transactional email providers are documented in the following locations:

File	Purpose	Link
README.md – Email section	Central list of free email services including transactional APIs, SMTP relays, and sandbox servers.	README – Email
.github/PULL_REQUEST_TEMPLATE.md	Guidelines for contributing new services, including temporary/disposable email generators used for testing workflows.	.github/PULL_REQUEST_TEMPLATE.md

The repository maintains a single Markdown file structure, with each service entry formatted as a bullet point linking directly to the provider's website and noting specific free-tier limits. Because the file is version-controlled on GitHub, the content is always up-to-date with a clear edit history.

Summary

• The ripienaar/free-for-dev repository maintains the definitive curated list of free email services for transactional emails in the README.md Email section.
• Resend, MailerSend, and Brevo offer the highest free-tier quotas for production transactional email, ranging from 3,000 to 9,000 emails per month.
• EtherealMail and Mailtrap provide unlimited or high-volume sandbox environments for testing SMTP integrations without delivering to real inboxes.
• Integration examples demonstrate Python (aiosmtplib), cURL (REST API), and Node.js (Resend SDK) implementations using credentials from the free tiers documented in the repository.

Frequently Asked Questions

What is the best free email service for high-volume transactional emails?

Sendpulse offers the highest free-tier limit at 15,000 emails per month, making it suitable for applications with moderate transactional volume, though it limits you to 500 subscribers. For pure transactional use without subscriber limits, Brevo provides 9,000 emails monthly with both SMTP and API access, while MailChannels offers 3,000 emails per month optimized for high-volume bulk delivery.

How do I test transactional emails without sending to real users?

The free-for-dev repository lists EtherealMail and Mailtrap specifically for this purpose. EtherealMail provides unlimited fake SMTP credentials—messages are accepted by the server but never delivered, instead being viewable through a private web interface. Mailtrap offers a sandbox environment with 3,500 emails per month and one inbox, capturing all outgoing mail from your development environment before it reaches real inboxes.

Can I use a custom domain with free transactional email tiers?

Yes, several providers in the free-for-dev list support custom domains on their free tiers. Resend explicitly allows one custom domain on their free tier of 3,000 emails per month, while AhaSend permits unlimited domains with their 1,000 emails per month allocation. MailerSend and Brevo also support domain authentication on free tiers, though you should verify current limits in the repository as quotas may change with provider policy updates.

Where is the transactional email list located in the free-for-dev repository?

The curated list resides in the Email section of the README.md file at the repository root. You can navigate directly to this section via the table of contents or by viewing the raw file at specific line references such as line 825 for entries like AhaSend. The repository also references email-related testing tools in .github/PULL_REQUEST_TEMPLATE.md, which mentions temporary email generators used for validating contribution workflows.

{
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    "instagit": {
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    }
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}