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Transactional email API and SMTP relay

Email your users are waiting for

Send sign-in codes, receipts and password resets from your own domain. Postilon signs, delivers and tracks each one, and tells your app what happened.

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3,000 free credits when you verify your first domain. No card needed.

One request to send

Postilon queues the email, signs it with your domain's key and delivers it through its own mail servers. A retried request with the same idempotency key never sends twice.

Quickstart
curl https://api.postilon.com/v1/emails \
  -H "Authorization: Bearer $POSTILON_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "from": "Acme <hello@acme.com>",
    "to": "jane@example.com",
    "subject": "Your sign-in code",
    "html": "<p>Your code is <strong>482913</strong>.</p>"
  }'

Everything transactional email needs

  • REST API and SMTP relay

    Send with one JSON request, or point your framework's SMTP settings at smtp.postilon.com.

  • Your domain, signed

    Every email is DKIM-signed with your domain's own key, with the SPF and DMARC records to match.

  • Webhooks for every event

    Signed events for deliveries, bounces, complaints, opens and clicks, as they happen.

  • Templates

    Keep subjects and bodies in Postilon and fill in each email's details with variables.

  • Suppression built in

    Addresses that bounce, complain or unsubscribe are never mailed again, and the credits come back.

  • Test keys

    Build against the real API with test keys: emails are rendered and reported, but never leave Postilon.

Pay for what you send

USD 4 per 10,000 emails, with every feature included. Buy credits when you need them; there is no subscription.

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