Send email over SMTP — no rewrite required
Point any app that speaks SMTP at smtp.unitpost.com and it flows through the same pipeline as our API — the same sending gate, tracking, webhooks, and dashboard. Change a config, not your code.
Copy, paste, send
One set of credentials
Generate a send-only credential in Settings → SMTP, drop it into your SMTP client, and you're delivering. TLS is mandatory — plaintext auth is refused.
| Host | smtp.unitpost.com |
|---|---|
| Username | unitpostfixed |
| Password | Your API keyneeds emails:send |
| Port 587 | STARTTLSsubmission |
| Port 465 | Implicit TLSSSL |
| Ports 2587 / 2465 | Aliasesif 587/465 blocked |
import nodemailer from "nodemailer";
const transporter = nodemailer.createTransport({
host: "smtp.unitpost.com",
port: 587, // STARTTLS
secure: false, // use port 465 + secure:true for implicit TLS
auth: {
user: "unitpost", // always "unitpost"
pass: process.env.UNITPOST_API_KEY, // your API key
},
});
await transporter.sendMail({
from: "you@yourdomain.com", // a verified domain
to: "customer@example.com",
subject: "Hello",
html: "<p>Sent via the Unitpost SMTP relay.</p>",
});Production-ready
An alternate front door, not a second-class one
SMTP isn't a bolt-on. It shares the exact send path as our REST API, so it inherits every guarantee.
TLS by default
STARTTLS on 587/2587 and implicit TLS on 465/2465. Auth over plaintext is refused — your key is a secret credential.
Shows in your dashboard
Every SMTP send lands in the same activity view as API sends, with delivery, open, click, and bounce status.
Webhooks just work
The same signed webhooks fire for SMTP messages — delivered, opened, clicked, bounced, complained.
Idempotent retries
Add a Unitpost-Idempotency-Key header and a retried delivery replays the original send, never a duplicate.
Same everything
No new mental model
SMTP is just another front door to the pipeline you already know. Every send — API or SMTP — shares one gate, one set of limits, one dashboard.
Same sending gate
Verified-domain checks, quotas, and suppression apply to SMTP exactly like the API — one writer, one set of rules.
Same tracking & webhooks
Delivered, opened, clicked, bounced, complained — every SMTP send shows up in the dashboard and fires the same signed webhooks.
Same limits & idempotency
Your plan's rate limits span API and SMTP. Set a Unitpost-Idempotency-Key header and retries never double-send.
Start sending email your users actually receive
Create a key, verify a domain, and send your first email in minutes — over the API or right from the dashboard.