# Using Cisco Prefix Lists Inside Route Maps for BGP Filtering

DevFeed: [Using Cisco Prefix Lists Inside Route Maps for BGP Filtering](<https://devfeed.tech/articles/using-cisco-prefix-lists-inside-route-maps-for-bgp-filtering-40149.md>)

Original publisher: [Read original article](<https://blog.j2sw.com/inetarch/bgp-filtering-prefix-lists-route-maps/>)

Author: j2sw

Published: 2026-08-11T14:48:44Z

Content type: tutorial

Language: en

Sources: [Justin Wilson (j2sw)](<https://devfeed.tech/sources/justin-wilson-j2sw.md>)

Topics: [BGP](<https://devfeed.tech/topics/bgp.md>), [Cisco](<https://devfeed.tech/topics/cisco.md>), [Network](<https://devfeed.tech/topics/network.md>)

Tags: [bgp](<https://devfeed.tech/tags/bgp.md>), [bgp-filtering](<https://devfeed.tech/tags/bgp-filtering.md>), [cisco](<https://devfeed.tech/tags/cisco.md>), [internet-architecture](<https://devfeed.tech/tags/internet-architecture.md>), [network-engineering](<https://devfeed.tech/tags/network-engineering.md>), [network-engineering-resources](<https://devfeed.tech/tags/network-engineering-resources.md>), [prefix-lists](<https://devfeed.tech/tags/prefix-lists.md>), [route-maps](<https://devfeed.tech/tags/route-maps.md>), [routing-policy](<https://devfeed.tech/tags/routing-policy.md>)

## AI overview

This tutorial explains how Cisco prefix lists and route maps work together for BGP filtering. Prefix lists define which routes match, while route maps apply actions such as permitting, denying, or modifying route attributes. It also describes route-map sequence order and implicit deny behavior.

## Source excerpt

Prefix lists define which BGP routes match a policy. Route maps use those matches to permit routes, deny them, or change attributes such as local preference. The post Using Cisco Prefix Lists Inside Route Maps for BGP Filtering appeared first on Justin Wilson (j2sw).