SMTP submission now available in beta
Cloudflare Email Service now supports authenticated SMTP submission on smtp.mx.cloudflare.net:465 as a third method to send transactional emails, alongside REST API and Workers bindings. This enables existing applications using SMTP libraries to integrate with Cloudflare's email service with identical limits and features.
You can now send emails through Cloudflare Email Service using authenticated SMTP submission on smtp.mx.cloudflare.net:465. SMTP joins the REST API and the Workers binding as a third way to send transactional email — useful for existing applications that already speak SMTP and language-native SMTP libraries (Nodemailer, smtplib, PHPMailer, JavaMail).
| Setting | Value |
|---|---|
| Host | smtp.mx.cloudflare.net |
| Port | 465 (implicit TLS) |
| AUTH | PLAIN or LOGIN |
| Username | api_token |
| Password | A Cloudflare API token (account-owned or user-owned) with Email Sending: Edit |
Submissions enter the same delivery pipeline as the REST API and Workers binding: identical limits, automatic DKIM and ARC signing, and shared dashboard logs.
Send your first email with a single command:
curl --ssl-reqd \ --url "smtps://smtp.mx.cloudflare.net:465" \ --user "api_token:<API_TOKEN>" \ --mail-from "welcome@yourdomain.com" \ --mail-rcpt "user@example.com" \ --upload-file mail.txtRefer to the SMTP reference for authentication details, response codes, and language-specific examples.
Source: original entry ↗
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