LLM Best Practices

Google Preferred Sources for site owners

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This is LLM Best Practices (llmbestpractices.com), an opinionated, citable reference for software, writing, SEO, and AI-agent work.

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Overview

Preferred Sources is a Google Search setting where a reader picks sites they want to see more of. Publishers do not apply for it; a reader chooses, and the site owner’s only lever is asking readers to choose. Google documents the feature and three ways to link to it in its preferred sources guide. Treat it as a loyalty feature for returning readers, not a ranking tactic.

Know what a reader gets after choosing your site

A reader who selects your site sees its content more often in Top Stories, marked with a “preferred” badge. Google’s guide says content can also carry the badge in AI Overviews and AI Mode for that reader. The preference applies only to the reader who set it; it changes nothing for anyone else. Google’s documentation publishes no figures on how much traffic or clicks a preference adds, so do not forecast with one.

Google’s documentation update log records the timeline: the guide for site owners (January 30, 2026), all languages (April 30, 2026), AI Mode and AI Overviews (May 27, 2026), and a custom button option (August 20, 2026).

  • Only a domain or subdomain can be a preferred source. example.com and news.example.com qualify; a subfolder such as example.com/blog does not.
  • For the AI Overviews and AI Mode badge, the site must be included in Search generative AI features in Search Console. Opting out there removes the badge in those surfaces. See ai-overviews.
  • Confirm the site appears by searching for it in Google’s source preferences tool.
  • Integration is optional. Readers can find and select an eligible site in the tool without any button on your pages.

Pick the integration by what it loads

Google offers three options. They differ mainly in what runs on your page.

OptionWhat you addWhat the visitor’s browser loads
Standard JavaScript buttonOne <script async> tag for Google’s publisher.js plus one <div google-add-preferred-source-btn>Google’s script on every page that carries the button, before anyone clicks
Advanced JavaScriptThe same script as an ES module or callback queue, wired to your own button designGoogle’s script on every page, with your styling
DeeplinkA plain link to https://www.google.com/preferences/source?q=example.comNothing until the reader clicks

Google labels the standard button as its recommended path. The deeplink is documented for cases where JavaScript is not possible, and works in newsletters and social posts as well as on the site.

<a href="https://www.google.com/preferences/source?q=example.com">
  Add example.com as a preferred source on Google
</a>

Use the deeplink when the site promises no third-party scripts. The JavaScript options make every page view request a Google-hosted script, which exposes each visit to a third party and adds a network request to the critical path (page-speed). The deeplink keeps the page static: Google sees the visit only when a reader deliberately follows the link to Google’s own tool.

This site uses the deeplink in its footer and on about, consistent with the no-third-party-requests posture in privacy. Google also supplies translated badge images; self-host one if you want a graphic, rather than hotlinking.

Ask returning readers, not first-time visitors

A preference only pays off for someone who will search for your topics again. Place the link where loyal readers look: the footer, the about page, the end of a newsletter. Skip interstitials and pop-ups that interrupt a first visit. News publishers get the most from it because Top Stories is the main surface; see news-seo.

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