Referring domains are the unique websites that link to your site. If backlinks are individual votes of confidence, referring domains are the sources of those votes. For example, if Website A links to you 10 times, that counts as 10 backlinks but only 1 referring domain.
Search engines, especially Google, look at referring domains to understand how many different websites trust your content. In general, a site with more high-quality referring domains is seen as more authoritative and credible than one with many backlinks from only a few sources.
What Referring Domains Really Mean
When SEO tools report your referring domains, they’re essentially showing how many unique websites link to you at least once. This matters because:
- A variety of domains shows broad trust, not just repeated links from one source.
- It helps search engines measure your site’s popularity across the web.
- It indicates that your content is authoritative enough to earn links from different audiences and industries.
In SEO terms, the number and quality of referring domains can influence your domain authority, organic rankings, and long-term visibility.
Referring Domains vs. Backlinks
These two terms are often confused, so here’s the difference:
Backlinks
- Total number of inbound links.
- One domain can create dozens or hundreds of backlinks.
Referring Domains
- Total number of unique websites linking to you.
- Multiple backlinks from one domain still count as a single referring domain.
Why this matters:
Google tends to value diversity of sources more than sheer link volume. Ten links from 10 different websites are usually more impactful than 50 links from the same site.
Why Referring Domains Matter for SEO
1. Strong Indicator of Authority
Search engines trust websites that have been “endorsed” by many reputable sources. More high-quality referring domains usually lead to stronger organic rankings.
2. Helps Content Compete in Competitive Niches
Pages with a variety of referring domains often outrank similar pages, especially in saturated industries like finance, health, and technology.
3. Reduces Risk of Manipulated Link Profiles
If your site has lots of backlinks but very few referring domains, it can look unnatural something search engines pay attention to.
4. Enhances Discoverability
Referring domains (especially authoritative ones) help search engines crawl and index your pages more effectively.
Types of Referring Domains
Not all referring domains carry the same weight. They generally fall into three categories:
1. High-Authority Domains
Government sites, universities, trusted media outlets, and industry leaders.
Impact: Very strong and highly valuable.
2. Mid-Authority Domains
Niche blogs, business websites, community resources.
Impact: Solid and natural, good for building a diverse link profile.
3. Low-Quality or Spammy Domains
Sites with thin content, link farms, or irrelevant pages.
Impact: Little value and potentially harmful if over-represented.
How to Increase High-Quality Referring Domains
1. Publish Linkable Content Assets
Examples include data studies, original research, tutorials, infographics, and helpful tools.
2. Outreach and Digital PR
Pitch your content to journalists, bloggers, and industry publications.
3. Guest Posting
Contribute valuable articles to relevant websites that link back to your content.
4. Build Relationships in Your Industry
Networking often leads to natural, long-term linking opportunities.
5. Fix Broken Links
Find pages linking to broken URLs and suggest your content as a replacement.
6. Create Resources Worth Citing
Glossaries, templates, checklists, and guides attract organic links over time.
Referring domain counts are less useful when:
- Making content quality decisions that do not involve domain authority
- Addressing technical SEO issues unrelated to authority
- Evaluating user experience or on page improvements
- You need behavioral data rather than backlink-related insights
Real-World Example
Imagine two websites:
- Site A has 500 backlinks from 8 domains
- Site B has 200 backlinks from 60 domains
Even though Site A has more backlinks, Site B is likely stronger from an SEO standpoint because more unique sites trust and reference its content.
How to Check Referring Domains
You can monitor your referring domains using popular SEO tools such as:
- Ahrefs
- Semrush
- Moz
- Majestic
- Google Search Console (indirectly through “Links” report)
These tools show not just the count, but also the quality, authority, anchor text, and growth of referring domains over time.
Practical Tips
- Aim for quality over quantity. A single authoritative link can outperform dozens of weak ones.
- Maintain a natural mix journals, blogs, resource sites, niche platforms, etc.
- Review your link profile regularly for toxic domains.
- Build content that naturally earns links instead of relying on quick-win tactics.
- Track new referring domains monthly to spot growth trends or issues.
Referring Domains FAQs
Are referring domains more important than total backlinks?
Yes. Search engines value the number of unique high-quality domains more than raw backlink count.
How many referring domains does a site need?
There is no ideal number. More important is earning relevant, authoritative domains that align with your industry.
Why do referring domains fluctuate?
Links get removed, pages get updated, sites shut down, or crawlers discover new links. Fluctuation is normal unless losses are significant.
Do nofollow links count as referring domains?
Yes. Nofollow links still contribute to domain diversity, visibility, and potential referral traffic, even if they pass limited ranking value.
Is it bad to have many links from a single domain?
Not inherently, but it offers diminishing SEO value compared to earning links from multiple high-quality domains.
How do I find new referring domains?
Use backlink analysis tools to identify opportunities, monitor competitors, and plan targeted outreach.