All integrations Email Infra

Postmark + MailKite

Postmark is a transactional email service known for deliverability. MailKite offers the same reliability with inbound-first architecture, unlimited free domains, and MCP-native AI agent support.

What you need

A verified domain with SPF + DKIM published
Your API key (mk_live_…)
Postmark account (optional — MailKite replaces or complements it)

Send email

Swap your SMTP host from Postmark to MailKite — same transactional focus, more features.

smtp-config

# MailKite as a Postmark alternative
# Same transactional focus, more features

SMTP Host: smtp.mailkite.dev
SMTP Port: 587
SMTP Username: mailkite
SMTP Password: mk_live_...
From: hello@yourdomain.com

# Postmark SMTP was:
# SMTP Host: smtp.postmarkapp.com
# Port: 587 (or 2525)
# Just swap the host and API key

Receive inbound email (optional)

Postmark charges extra for inbound parsing. MailKite includes it free.

inbound-comparison

# MailKite inbound webhook
# POST https://your-endpoint.com/webhook
# Payload: { from, to, subject, text, html, attachments }

# Postmark's inbound parsing is a paid add-on
# MailKite includes inbound parsing free

Test it

Swap your SMTP host and send a test email.

terminal

# Quick test
echo "Test" | swaks --to test@example.com --from hello@yourdomain.com \
  --server smtp.mailkite.dev --port 587 \
  --auth USER=mailkite --auth-password mk_live_...

Troubleshooting

Postmark requires sender signatures for each "From" address. MailKite verifies via SPF + DKIM — automated setup.
Postmark's inbound parsing requires a paid plan. MailKite includes inbound free.
If migrating, update the SMTP host and API key — same interface.

See the SMTP relay docs for the full connection reference, or all integrations for other platforms.