SMTP Server

In addition to our modern HTTP REST API, HiSend provides a native, fully compatible SMTP server interface. This allows you to easily drop HiSend into existing legacy applications, standard email clients, or platforms that don't natively support custom API integrations (like WordPress, Ghost, or older CRM software).

Connection Details

To connect to our SMTP relay, use the following credentials in your application or client.

Example: Node.js (Nodemailer)

If you are using Node.js but prefer standard SMTP protocols over our dedicated @hisend/sdk, you can configure the popular nodemailer package like this:

const nodemailer = require("nodemailer");

const transporter = nodemailer.createTransport({
  host: "smtp.hisend.app",
  port: 587,
  secure: false,
  auth: {
    user: "hisend",
    pass: "YOUR_API_KEY",
  },
});

async function main() {
  const info = await transporter.sendMail({
    from: '"Acme Corp" <hello@yourverifieddomain.com>',
    to: "customer@example.com",
    subject: "Hello via SMTP",
    text: "This email was routed through the HiSend SMTP servers.",
    html: "<b>This email was routed through the HiSend SMTP servers.</b>",
  });

  console.log("Message ID: %s", info.messageId);
}

Security & Deliverability

Emails sent through the SMTP interface undergo the exact same robust deliverability processing, DKIM signing, and reputation checking as emails sent through the REST API. Your tracking metrics in the HiSend Dashboard will accurately reflect both SMTP and REST outbound volumes.