---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/sendgrid/glossary/mua#article
headline: Mail User Agent (MUA)
description: "*Internet standard*. An app that you use to compose and send email messages."
url: https://www.twilio.com/docs/sendgrid/glossary/mua
inLanguage: en
dateModified: 2025-11-07T21:55:06.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# Mail User Agent (MUA)

*Internet standard*. An app that you use to compose and send email messages.

Examples of a Mail User Agent (MUA) include Gmail, Apple Mail, and Microsoft Outlook.