---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/sendgrid/glossary/smtp-server#article
headline: SMTP Server
description: "*Internet standard*. An app or server that sends email and reacts to response codes from receiving servers."
url: https://www.twilio.com/docs/sendgrid/glossary/smtp-server
inLanguage: en
dateModified: 2026-07-23T16:57:51.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# SMTP Server

*Internet standard*. An app or server that sends email and reacts to response codes from receiving servers.

An SMTP server sends email using the [Simple Mail Transfer Protocol (SMTP)][smtp]. An SMTP server doesn't describe the physical (or virtual) server, but the [application][] on it that runs in the background waiting to send mail.

[application]: https://www.twilio.com/en-us/blog/insights/what-is-an-smtp-server

[smtp]: /docs/sendgrid/glossary/smtp