---
title: Add a prefix to Advanced DDoS Protection · Cloudflare DDoS Protection docs
description: "To add a prefix to Advanced DDoS Protection:"
lastUpdated: 2025-09-03T18:12:42.000Z
chatbotDeprioritize: false
source_url:
  html: https://developers.cloudflare.com/ddos-protection/advanced-ddos-systems/how-to/add-prefix/
  md: https://developers.cloudflare.com/ddos-protection/advanced-ddos-systems/how-to/add-prefix/index.md
---

To add a [prefix](https://developers.cloudflare.com/ddos-protection/advanced-ddos-systems/concepts/#prefixes) to Advanced DDoS Protection:

1. In the Cloudflare dashboard, go to the **L3/4 DDoS protection** page.

   [Go to **DDoS Managed Rules**](https://dash.cloudflare.com/?to=/:account/network-security/ddos)

2. Go to **Advanced Protection**.

3. Under **General settings** > **Prefixes**, select **Edit**.

4. Expand the **Add existing prefix** section and select **Add** next to the prefix you wish to add.\
   Alternatively, enter a prefix and (optionally) a description in **Prefix** and **Description**, respectively, and select **Add**.

Note

The **Add existing prefix** list will not display leased prefixes, but you can add them manually in the Cloudflare dashboard or [using the API](https://developers.cloudflare.com/ddos-protection/advanced-ddos-systems/api/). You cannot add [delegated prefixes](https://developers.cloudflare.com/byoip/concepts/prefix-delegations/) to Advanced TCP Protection.
