Send email from Next.js over SMTP

Send from a Next.js Route Handler with Nodemailer pointed at Unitpost SMTP. Keep the API key on the server — never in a Client Component.

What are the SMTP settings?

Host	smtp.unitpost.com
Username	unitpost(always this literal value)
Password	Your Unitpost API key(must carry emails:send)
Port (STARTTLS)	587(or 2587 if blocked)
Port (implicit TLS)	465(or 2465 if blocked)
From address	Any address on a verified domain

How do I set it up?

Install Nodemailer

Shell

npm install nodemailer
npm install -D @types/nodemailer

Create a Route Handler

Server-only. The from address must be on a verified domain.

TypeScript

import nodemailer from "nodemailer";
import { NextResponse } from "next/server";

const transporter = nodemailer.createTransport({
  host: "smtp.unitpost.com",
  port: 587,
  secure: false,
  requireTLS: true,
  auth: {
    user: "unitpost",
    pass: process.env.UNITPOST_API_KEY,
  },
});

export async function POST() {
  await transporter.sendMail({
    from: "you@yourdomain.com",
    to: "customer@example.com",
    subject: "Hello from Next.js",
    html: "<p>Sent via SMTP.</p>",
  });
  return NextResponse.json({ ok: true });
}

Verify delivery
Check Activity. Same transport as the Nodemailer guide — this page is the Next.js wiring.