Guide 7 min read Updated April 2026

Best Free Transactional Email Services in 2026 (Up to 12,000 Emails/Month)

Whether you're prototyping, running a side project, or launching a startup, a generous free tier lets you send transactional emails without a credit card. Here's the complete comparison of what's actually free in 2026.

What counts as a "free tier"?

A genuine free tier is a permanent plan that gives you a fixed amount of emails every month, indefinitely, with no credit card required. This is different from a free trial (time-limited) or a conditional free tier (requires AWS hosting).

In this guide, we only count services that offer a permanent free tier with no credit card required and no expiration date.

Free tier comparison table

Service	Monthly	Daily cap	Card	SMTP	DKIM	GDPR
Emitlo Best overall free tier	12,000/mo	400/day	No	✅	Double	✅
Mailjet EU-based, daily cap	~6,000/mo	200/day	No	✅	Single	✅
Brevo Low daily cap risk	~9,000/mo	300/day ⚠️	No	✅	Single	✅
MailerSend EU-based, low volume	3,000/mo	None	No	✅	Single	✅
Resend API only, no SMTP	3,000/mo	None	No	❌	Single	⚠️
Amazon SES AWS-hosted only, complex	62,000/mo*	None	Required	✅	Single	⚠️
Postmark Trial only, not a free tier	100 emails	None	No	✅	Single	⚠️

* Amazon SES free tier only applies if hosted on AWS EC2/Lambda.

Emitlo's free tier gives you 12,000 emails/month — no credit card, no daily cap surprises, with full deliverability monitoring included. Start free →

The daily cap problem

Daily caps are the hidden trap of free email tiers. Brevo limits you to 300 emails/day and Mailjet to 200/day. These numbers sound fine for normal usage — but consider these scenarios:

⚠A password reset storm: 500 users request password resets in one hour. With Brevo, 200 emails queue and users wait.
⚠A batch notification: you send order confirmations for 400 orders placed overnight. With Mailjet, 200 emails are delayed.
⚠A marketing blast: you send a product update to 1,000 users. With Brevo, it takes 3+ days to complete.

Emitlo's free tier has a 400/day cap with 12,000/month total. You can send all 12,000 in a single day if needed — the monthly cap is the only constraint.

Emitlo free tier in detail

Emitlo's free plan includes:

✓400 emails/day · 12,000 emails/month
✓50 emails/hour rate limit
✓3 sending domains
✓3 API/SMTP credentials
✓14 days log history
✓10 MB max attachment size
✓Full SMTP + REST API
✓Double DKIM signing
✓SPF, DKIM, DMARC auto-configured
✓Real-time deliverability dashboard
✓Automatic bounce & complaint handling
✓Webhooks for all events
✓No credit card required
✓No expiration date

When to upgrade to paid

Consider upgrading from Emitlo's free tier when:

→You're consistently sending more than 400 emails/day or 12,000/month
→You need dedicated IPs for full reputation control
→You need more than 14 days of log history
→You need more than 3 sending domains
→You need higher hourly rate limits for burst sending
→You need SLA guarantees for production-critical email

Emitlo's Pro plan is pay-as-you-go at $0.15/1,000 emails — no monthly commitment, no tier surprises.

Start free — no credit card, no daily cap surprises

12,000 emails/month (400/day) · SMTP + API · Double DKIM · Full deliverability dashboard

Get started free → See all comparisons

Frequently Asked Questions

What is the best free transactional email service?

Emitlo offers the best free tier: 12,000 emails/month (400/day cap) with no credit card required, full SMTP and API support, double DKIM signing, and a complete deliverability dashboard. It's the most generous permanent free tier available for transactional email.

What is the difference between a free tier and a free trial?

A free tier is a permanent plan that gives you a fixed amount of emails every month, indefinitely. A free trial is a time-limited or volume-limited offer that expires. Emitlo, Mailjet, Brevo, MailerSend, and Resend offer permanent free tiers. Postmark offers only a 100-email trial. Amazon SES offers a free tier only if your application is hosted on AWS.

What is a daily cap and why does it matter?

A daily cap limits how many emails you can send per day. Brevo's free tier is 300/day and Mailjet's is 200/day. If you have a traffic spike — a password reset storm, a batch notification — you'll hit the cap and emails will queue or fail. Emitlo's free tier has a 400/day cap with 12,000/month total, which is more generous and less likely to cause issues.

Do I need a credit card for a free transactional email service?

Emitlo, Mailjet, Brevo, MailerSend, and Resend all offer free tiers with no credit card required. Amazon SES requires an AWS account (which requires a credit card). Mailgun requires a credit card for its trial.

When should I upgrade from a free tier to a paid plan?

Consider upgrading when: (1) you're consistently hitting your daily or monthly cap, (2) you need dedicated IPs for better reputation control, (3) you need longer log history (Emitlo free tier: 14 days), (4) you need more sending domains or credentials, (5) you need higher rate limits for burst sending.

Is the Amazon SES free tier really free?

Amazon SES offers 62,000 emails/month free, but only if your application is hosted on AWS EC2 or Lambda. If you're not on AWS, standard pricing applies ($0.10/1k). Additionally, SES requires a credit card, has a sandbox that restricts sending until you request exit, and has no built-in deliverability dashboard.