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11 Best Email Tools With Permanent Free Tiers (2026), Tested

Limited to providers with a permanent free tier as of the last check. Trials excluded.

criteria

  1. 01

    Sender

    Marketing

    2,500 subscribers and 15,000 emails/mo on a permanent free plan. Strongest free marketing tier in this set.

  2. 02

    SendPulse

    Transactional Marketing

    12,000 transactional SMTP emails/mo is unusually generous, though the free plan is hourly capped.

  3. 03

    Mailjet

    Transactional Marketing

    6,000/mo capped at 200/day. Permanent and useful for steady low-volume sends.

  4. 04

    Loops

    Marketing Transactional

    Unlimited emails on the Free plan within a 1,000-contact ceiling. Different model: optimal when your contact list grows slowly but your volume is high.

  5. 05

    Brevo

    Transactional Marketing

    300/day permanent. Best for low daily volumes that do not spike on launch day.

  6. 06

    Mailtrap

    Transactional Testing

    4,000/mo permanent on the sending side, plus a free testing tier.

  7. 07

    Resend

    Transactional

    3,000/mo permanent on a single domain.

  8. 08

    MailerSend

    Transactional

    3,000/mo permanent.

  9. 09

    Plunk

    Self-hosted Marketing

    3,000/mo on hosted free plan, or self-host for unlimited.

  10. 10

    Amazon SES

    Transactional

    New accounts get up to $200 in AWS credits for six months. The old 62,000/mo-from-EC2 allowance is gone.

  11. 11

    SMTP2GO

    Transactional

    1,000/mo permanent, no daily cap.

All 11 compared

Every provider in this ranking against the priorities teams building autonomous agents weigh. Free tier and entry price sit with each pick above.

ProviderInbound parsingIdempotency keysWebhooksOperating sinceEvent streamBest published rate per 1,000Batch sendingSDKsMulti-tenant
SenderNoNoYes2012YesTiers not published in comparable formYesNoneNo
SendPulseNoNoYesNot publishedYesTiers not published in comparable formYesNoneNo
MailjetYesNoYesNot publishedYesTiers not published in comparable formYesnode, python, go, ruby, php, java, dotnetYes
LoopsNoNoYes2022YesTiers not published in comparable formYesnode, python, go, ruby, phpNo
BrevoYesNoYes2012YesTiers not published in comparable formYesnode, python, go, ruby, php, java, dotnetNo
MailtrapNoNoYes2014YesTiers not published in comparable formYesnode, python, go, ruby, php, elixirYes
ResendYesYesYes2023Yes$0.35Yesnode, python, go, ruby, php, rust, java, elixir, cliNo
MailerSendYesNoYes2020YesTiers not published in comparable formYesnode, python, go, ruby, phpYes
PlunkNoNoYesNot publishedYesTiers not published in comparable formYesnode, pythonNo
Amazon SESYesNoNo2011Yes$0.10Yesnode, python, go, ruby, php, java, rust, dotnetNo
SMTP2GOYesNoYes2006YesTiers not published in comparable formYesnode, python, go, ruby, phpYes

If you are teams building autonomous agents

An agent stack treats email as a two-way primitive. Inbound has to arrive as structured JSON a tool call can consume, sends have to be safe to retry when a model loop repeats itself, and every action needs an audit trail. A provider without inbound parsing only solves half the problem.

The order above is the general editorial ranking. Re-sorted against inbound parsing, idempotency keys, and webhook coverage, the shortlist for inbound parsing into tool calls and model-generated sends that must not duplicate becomes Resend, Mailjet, and MailerSend. That differs from the headline order, which weighs all audiences together.

How rankings are produced →