Referring Domains: What They Are and Why They Matter More Than Backlinks

When you open a backlink report, two numbers sit side by side: backlinks and referring domains. The second one is the one SEO professionals look at first. This guide explains what a referring domain is, how it differs from a backlink, why diversity matters for Google and for the AIs, how to check yours and how to get more.

What is a referring domain?

A referring domain is a website (counted at the domain level) from which at least one link points to your site. If example-blog.com links to you once or a hundred times, it still counts as one referring domain.

Most tools count at the root domain level, so blog.example.com and shop.example.com are often grouped under example.com, although some tools also report subdomains or IP addresses separately. Every tool uses its own crawler, so the figures from Ahrefs, Semrush, Moz or Majestic will never match exactly: compare like with like, using the same tool over time.

The term comes from the referrer, the site that sends a visitor or a link to yours. A backlink is the link itself; the referring domain is the site that hosts it.

What is the difference between referring domains and backlinks?

Backlinks count links, referring domains count the sites they come from. A site can have thousands of backlinks from a handful of domains, or a few hundred backlinks spread across hundreds of domains, and the second profile is usually stronger.

A large gap between the two numbers often comes from sitewide links (a link in the footer of every page of a partner site). These are not harmful in themselves, but they add little compared with a link from a new, independent site.

Why do referring domains matter for SEO?

Each new referring domain is a separate source recommending your content, and search engines treat independent recommendations as a signal of relevance and trust. Google states in its link best practices that it uses links as a signal to judge the relevance of pages and to discover new pages.

• Correlation with rankings. Backlinko's analysis of 11.8 million Google results, run with Ahrefs data in 2020, found that the number of referring domains correlated with higher positions, and that the first result had on average 3.8 times more backlinks than results 2 to 10.
• Most pages without links get no traffic. Ahrefs' 2023 study of about 14 billion pages found that 96.55% get no traffic from Google, and identified the lack of backlinks as one of the main reasons pages fail to rank for competitive terms.
• Discovery and crawling. Links from many sites help crawlers find and revisit your pages faster.

These studies show correlations, not a guaranteed effect: content quality and search intent still decide whether a page deserves to rank. But on competitive keywords, pages with few referring domains rarely beat pages with many relevant ones. Our glossary entry on domain authority explains how tools turn this link data into a single score.

Why does referring domain diversity matter?

Because a varied profile looks natural and spreads the signal across many independent sources, while a concentrated one is fragile and easier to discount. Diversity has several dimensions:

• Number of sites: more independent domains, not more links from the same ones.
• Topical relevance: sites from your industry carry more weight than random directories.
• Quality: real sites with their own audience and traffic, not pages built only to sell links.
• Link types: editorial mentions in articles, resources, partners, press, a reasonable share of nofollow links.
• Anchors: a mix of brand names, URLs and descriptive phrases, which our guide to anchor text details.

Google's spam policies target link schemes, including excessive link exchanges and networks of sites built to pass links. A profile where dozens of domains share the same owner adds little real value and carries risk.

How do you check your referring domains?

Use a backlink checker, filter the list by domain, then sort by relevance and quality. The steps are the same whatever the tool:

1. Enter your domain in a backlink tool, for example our free backlink analysis tool, Ahrefs, Semrush or Majestic.
2. Open the referring domains report rather than the backlinks list.
3. Sort by authority or traffic to see your strongest supporters.
4. Check new and lost domains over the last months: a sudden drop can come from a deleted page or a redesign.
5. Repeat the analysis on your three to five main competitors and list the domains that link to them but not to you.

Google Search Console also lists the top linking sites in its Links report. The data is partial, but it comes directly from Google.

How do you get more referring domains?

Create content other sites want to cite, then make sure the right people see it. The most reliable methods:

• Publish citable resources: original data, studies, free tools, templates and complete guides earn links over time.
• Target competitors' referring domains: sites that already link to similar content are the most likely to link to yours.
• Digital PR: give journalists and bloggers useful data or expert comments.
• Reclaim mentions: ask sites that mention your brand without a link to add one.
• Fix broken links: offer your page as a replacement for dead resources on relevant sites.
• Partners and community: suppliers, associations, events and podcasts often link to their partners.

Avoid bought link packages from unrelated sites and reciprocal link schemes. Our guide on how to get backlinks details each method step by step.

Do referring domains matter for AI visibility?

Yes, indirectly: the sites that link to you are often the same sites that mention you, and these mentions shape what ChatGPT, Gemini, Perplexity and Claude say about your brand. AI assistants that search the web retrieve pages that rank well in search results, and their models learn from content published across many sites.

A brand that is cited by many independent, relevant domains has more chances to appear as a recommendation in AI answers than a brand that only talks about itself. The work is the same: earn mentions and links on varied, trusted sites in your topic.

Conclusion

A referring domain is a unique site that links to you, and the number of relevant, independent referring domains matters more than the total number of backlinks. Track it with one tool over time, compare it with the pages that outrank you, and grow it with content worth citing and links from varied sites in your industry.

Sorank helps you obtain natural backlinks automatically, placed in real articles of sites in the same topic and always one-way, while it publishes optimized articles on autopilot. See how it works on the backlinks page, or compare the plans with a 3-day free trial.