SMTP Relay

Drop-in SMTP relay for the stack you already have

Point your existing mail library, CMS or legacy app at MailCraft's SMTP relay and get modern deliverability, webhooks and analytics — without changing a line of application code.

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How it works

1
Grab your SMTP credentials
Generate an SMTP username and password scoped to a sending domain.
2
Update your mail config
Swap the host, port, username and password in whatever already sends your mail.
3
Send exactly like before
No API integration required — your existing SMTP calls just start flowing through MailCraft.
4
Watch it in the dashboard
Every relayed message gets the same logs, webhooks and analytics as the API.

smtp-config.env

# Drop these into your existing mailer config
SMTP_HOST=smtp.mailcraft.host
SMTP_PORT=587
SMTP_ENCRYPTION=tls
SMTP_USERNAME=sc_smtp_a1b2c3
SMTP_PASSWORD=••••••••••••••••

# Laravel: config/mail.php / .env
MAIL_MAILER=smtp
MAIL_HOST="${SMTP_HOST}"
MAIL_PORT="${SMTP_PORT}"
MAIL_USERNAME="${SMTP_USERNAME}"
MAIL_PASSWORD="${SMTP_PASSWORD}"

TLS on ports 587 and 465 Same DKIM signing as the API Same logs, webhooks and analytics Works with any SMTP library

No migration required

Modern deliverability for the mail you already send

Keep your mailer, your CMS and your legacy app — change four settings and everything else just gets better.

Drop-in credentials

Swap host, port, username and password in your existing config — no API integration, no redeploy of new code.

One pipeline

Relayed mail gets the same signing, suppression and rate limits as native API sends.

Full visibility

Every relayed message shows up in the dashboard with delivery events and webhooks, same as the API.

What's included

Everything in SMTP Relay

Live on your account the moment you sign up — nothing to request or provision.

TLS-secured relay on ports 587 and 465

Works with any SMTP library — Nodemailer, PHPMailer, Laravel Mail, msmtp, Postfix

Identical deliverability and DKIM signing as the REST API

Per-sender and per-domain rate limits

Bounce and complaint webhooks, same as native API sends

Shared IPs by default, dedicated IPs available on higher volume

Pairs well with the rest of MailCraft

SMTP Relay is one piece of the stack — reach for these when you need more.

Ready to try SMTP Relay?

Create a free account and send your first email — through the API, SMTP, or an MCP-connected AI agent — in minutes. No credit card required.

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