How Backlinks Influence AI Search Visibility in 2025: What the Semrush Study Reveals (and My Own Results)

The SEO world has been asking the same question for months.

Do backlinks still matter now that AI search is rewriting how people discover information?

Semrush released one of the most important studies of 2025 on this topic, the Backlinks & AI Search Study, and the findings are clear:

• Backlinks absolutely matter in the age of AI.
• Site Authority matters even more.
• Brand recognition is now a ranking factor for LLMs.

And after running the same analysis on brimco.io, we saw the exact patterns firsthand.

This blog breaks down what the Semrush study found, how backlinks influence AI search systems, and how our own site’s performance aligns with this new reality.

Why Backlinks Still Matter (Even in an AI-Dominated Search World)

A common belief is that AI search engines (ChatGPT Search, Google AI Overview, Perplexity, Gemini, etc.) rely less on traditional ranking factors, such as backlinks.

But Semrush’s data proves the opposite, even recent results I have seen from link building for some of the websites I do SEO on.

According to the study:

• Authority Score has the strongest correlation with AI visibility.
• Unique referring domains matter more than total link volume.
• High-authority backlinks dramatically increase the chances of being cited by AI systems.

This means backlinks are no longer just about ranking on Google.
They’re about training AI models to trust your brand.

What Are these Semrush Findings?

Here are three critical findings from the Semrush study.

1. Authority Score Has the Highest Impact on AI Visibility

One of the most striking charts from the study shows this:

Authority Score = the #1 predictor of whether AI search engines will cite your content.

Across LLM platforms:

• ChatGPT
• Perplexity
• Gemini
• Google AI Overviews

Websites with higher Authority Scores consistently received more citations.

This is important because LLMs don’t use “rankings” the way Google does.
Instead, they rely on:

• Trustworthiness
• Source authority
• Citation consistency across the web

In other words, Backlinks are now reputation signals for AI.

2. AI Mentions Heavily Favor High-Authority Sites

The Semrush study included an “AI Mentions by Authority Tier” study. From their research, the following was the result.

• Low-authority domains received 0–4 citations.
• Mid-tier domains received 5–15 citations.
• The top authority tier (Tier 10) received 79+ citations.

This is a massive gap. The question is, is your brand a part of these high citations? On all the websites I am doing SEO for these days, one of our main objectives is to get our pages cited. And it is possible to achieve this.

Semrush helps us get this data clear through the Semrush One plan, which gives us some insight into how our brands are performing on AI Search.

The results of the research have shown a crucial truth and why we should be optimizing LLMs.

AI search engines rely on established, trusted sources far more than traditional Google results do.

This also means

New websites can get organic traffic, but may struggle to get AI visibility without backlinks.

But it doesn’t mean that’s the end for those brands.

Writing authoritative content and building your link profile with high-quality links will boost your site’s authority and drive AI Mentions.

Look at the results below from one new website.

From writing less than 10 authoritative blogs and gaining a few links, the Authority Score grew by 4 points, and Ai mentions also grew. Double the number of Page citations in one month.

3. Image Links Play a Bigger Role Than Expected

One of the surprising insights from the study:

Image backlinks have nearly the exact correlation with AI visibility as text-based backlinks.

This makes sense when you think about how AI models interpret content.

Images provide:

• Entity reinforcement
• Contextual signals
• Visual confirmation of topics

So if your images appear across authoritative sites:

AI systems learn:

• Who you are
• What topics are you associated with
• Whether your brand should be included in their responses

Image links seem to have a strong relationship with Ai visibility even more than text links sometimes.

Case Study: How Backlinks Improved AI Visibility for Brimco.io

Over the past several months, we’ve been investing in both backlink building and backlink earning for Brimco.io with my team at Propello.

And the results mirror the Semrush study perfectly.

Backlink Growth for Brimco.io

According to our Semrush Backlink Analytics:

• Referring domains grew from ~750 to 1,200+ during the year.
• The most substantial growth happened during months when we published consistent thought‑leadership content.
• 76% of all new backlinks came from low- to mid-authority sources.
• High-authority wins included Wikipedia.

The last one is significant, even if it’s a nofollow link; it seems to have an impact on the site’s authority.

Wikipedia is one of the highly weighted sources in how LLMs evaluate source authority.

What’s even more interesting: Most of our backlinks were earned, not built.

Over 79% of our backlinks came in naturally, without outreach.

This indicates strong:

• Topic expertise
• Content relevance
• Brand growing reputation

This pattern is precisely what Semrush describes as a key marker of AI-trusted brands.

What is The Impact on AI Visibility

Now here’s where it gets exciting.

We checked our AI Visibility Report in Semrush.

Here’s what changed:

• AI mentions increased from 5 to 10
• Cited pages increased by 41 new URLs
• Monthly AI audience jumped to 306,800 (+305,700)

Even though our visibility score is still in the “Low” category (18/100), the trend is undeniable:

Quality Backlinks result in higher trust, more AI citations, and higher AI visibility.

This confirms what the Semrush study found.

Why This Matters for the Future of SEO

SEO is changing, fast.

But the fundamentals are not disappearing.
They’re evolving.

In the age of AI search:

• Backlinks = Trust signals
• Authority = Eligibility for AI citation
• Content clusters = Entity building for LLMs
• Brand mentions = Semantic reinforcement

Google rankings will always matter. But now there are new sources of Traffic that you shouldn’t ignore, in some cases, Bing and Yahoo overtake Google as traffic sources.

But AI search engines now represent a second search ecosystem.

If you want to appear in:

• ChatGPT Search
• Perplexity
• Google AI Overviews
• Gemini
• Copilot

Then you must invest in:

• Authority building
• Link earning
• Entity SEO
• High-quality, expert-driven content

Final Thoughts

The debate about whether backlinks still matter in the age of AI search can finally end.

They do.

They always have.

But now, in the era of AI search, they matter in a different and even deeper way.

Backlinks aren’t just about improving rankings.

They are about teaching AI systems who they can trust.

And the brands that understand this shift early will own the next decade of search.