---
title: MX/Inline deployment · Cloudflare Zero Trust docs
description: With pre-delivery deployment, also known as Inline deployment, Email Security evaluates email messages before they reach a user's inbox.
lastUpdated: 2025-04-10T10:40:28.000Z
source_url:
  html: https://patricia-pcx17119-l7-overrides.preview.developers.cloudflare.com/cloudflare-one/email-security/setup/pre-delivery-deployment/mx-inline-deployment/index.md
  md: https://patricia-pcx17119-l7-overrides.preview.developers.cloudflare.com/cloudflare-one/email-security/setup/pre-delivery-deployment/mx-inline-deployment/
---

With pre-delivery deployment, also known as Inline deployment, Email Security evaluates email messages before they reach a user's inbox.

Email Security becomes a hop in the SMTP processing chain and physically interacts with incoming email messages. Based on your policies, various messages are blocked before reaching the inbox.

When you choose an inline deployment, you get the following benefits:

* Messages are processed and physically blocked before arriving in a user's mailbox.
* Your deployment is simpler, because any complex processing can happen downstream and without modification.
* Email Security can modify delivered messages, adding subject or body mark-ups.
* Email Security can offer high availability and adaptive message pooling.
* You can set up advanced handling downstream for non-quarantined messages with added X-headers.

![Inline deployment diagram](https://developers.cloudflare.com/_astro/CF_A1S_Deployment_Inline_Diagrams.DO7lbMY8_1kLRgP.webp)
