What are Referrers and Channel Types?

Cloud On-Premise

Referrers help Matomo identify where visitors come from, such as search engines, social networks and other websites. Matomo uses available referrer and campaign information to classify visits into acquisition channels. For example:

  • When someone clicks a link to your site in a news article, the news website is recorded as the referrer.
  • If a visitor discovers your site through a Google search, Google is the referrer.
  • A visitor arrives at your site by clicking a link in a Facebook post, Facebook becomes the referrer.
  • When someone types your URL into the address bar or uses a bookmark, no external source is recorded, and the visit is categorised as a direct entry.

Identifying which pages frequently receive referral traffic helps you optimise high-performing entry points and improve underperforming channels to increase engagement and conversions.

Channel Types in Matomo

Log in to Matomo and open Acquisition > All Channels. Referrers are automatically categorised into the following channel types with details of each referrer.

channel types report

AI Assistants

Visits that Matomo identifies as originating from recognised AI tools such as ChatGPT, Copilot, Gemini, or Claude are grouped under the AI Assistants channel type. Classification depends on the source information available to Matomo.

Search Engines

Visits that originate from organic searches in search engines such as Google, Bing, DuckDuckGo, or Yahoo.

Campaigns

Visits from links containing recognised campaign parameters, such as mtm_campaign or utm_campaign used in email campaigns, paid ads, and banners.

Campaign information generally takes precedence over search engine, social network and website referrers. However, from Matomo 5.5.0 (October 2025), traffic identified as coming from an AI assistant is classified under AI Assistants, even when campaign parameters are present. Learn more about Campaign Tracking.

Websites

Visitors who arrive after clicking a link on another site, such as a blog, directory, or affiliate site.

Social Networks

Traffic coming from social media platforms like Facebook, X, Instagram, or LinkedIn.

Direct Entry

Visits where Matomo cannot identify a usable external referrer or recognised campaign information may be classified as Direct Entry. This includes visitors who type your URL into their browser, use a bookmark or follow links that do not provide usable referral information, such as some links in desktop applications, emails or PDF documents.

Why Referrers Matter

Referrer data is essential in web analytics as it reveals where your visitors are coming from.

  • It helps you understand how users arrive at your site, so you can evaluate the performance of your traffic sources.
  • Identify which sources consistently drive visits such as search engines, partner websites, or social media platforms. This information supports the management and development of valuable referral relationships.
  • Use referrer insights to focus on your most effective channels and discover new channels.
  • Optimise content placement, refine ad creations, or prioritise partnerships based on performance.
  • Track which campaigns generate the most traffic and evaluate the success of your acquisition strategies.
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