SSL certificates and SEO: what you need to know

If you're serious about SEO, you've probably heard that HTTPS is a ranking factor. But how much does it really matter? Is SSL just a checkbox to tick, or does it have a meaningful impact on your search visibility?

Let's cut through the noise and look at what we actually know about SSL certificates and SEO.

Google's official position

Google has been remarkably clear about their stance on HTTPS. In August 2014, they published a blog post titled "HTTPS as a ranking signal," explicitly stating that they were giving a ranking boost to secure websites.

At the time, Google described it as a "lightweight" signal, affecting fewer than 1% of global queries. But they also said they might strengthen it over time, "because we'd like to encourage all website owners to switch from HTTP to HTTPS to keep everyone safe on the web."

Since then, Google has followed through on that promise. While they don't publish exact details about their algorithm, the consensus among SEO professionals is that HTTPS has become increasingly important.

In 2020, Google announced that page experience signals (including HTTPS) would become part of their ranking criteria. This further cemented the role of SSL in search optimization.

How much does HTTPS actually matter?

Here's the honest answer: HTTPS alone won't rocket you to the top of search results. If your content is mediocre and your site has poor backlinks, adding SSL won't fix that.

But all else being equal, HTTPS provides an advantage. In competitive niches where multiple sites have similar content and authority, the presence or absence of SSL can be the tiebreaker.

Think of it like this: HTTPS is table stakes. It won't win you the game, but not having it can definitely lose you points.

Several studies have attempted to quantify the ranking impact of HTTPS. While results vary, most find a positive correlation between HTTPS and higher rankings. Whether that's causation or correlation (perhaps sites that invest in SSL also invest in other SEO best practices) is debatable, but the pattern is clear.

The indirect SEO benefits of SSL

Beyond the direct ranking signal, SSL provides several indirect benefits that can improve your SEO performance.

First, there's user behavior. Visitors who see security warnings are more likely to bounce immediately. High bounce rates send negative signals to search engines about your content quality. By preventing these warnings, SSL helps keep visitors on your site longer.

Second, there's referral data. When traffic passes from an HTTPS site to an HTTP site, the referral information is stripped. This means you lose valuable data about where your visitors come from. When both sites use HTTPS, referral data is preserved, giving you better analytics for SEO decision-making.

Third, there's trust and conversion. Users who trust your site are more likely to engage with it—sharing content, linking to it, returning for future visits. All of these behaviors can indirectly boost your SEO through increased engagement and backlinks.

Chrome's influence on user behavior

Google controls not just the dominant search engine but also the dominant web browser. Chrome's market share hovers around 65% globally, giving Google enormous power to shape user behavior.

Chrome has become increasingly aggressive about warning users about insecure sites. The "Not Secure" label in the address bar is just the beginning. For sites that contain forms, Chrome shows more prominent warnings. For sites that ask for passwords or credit card information over HTTP, the warnings are even more severe.

These browser warnings affect user behavior in ways that impact SEO. Users who see warnings are more likely to leave, less likely to engage, and less likely to convert. The resulting behavioral signals can negatively impact your search rankings, creating a vicious cycle.

Mobile-first indexing and HTTPS

Google now uses mobile-first indexing for the majority of websites, meaning they primarily use the mobile version of your site for ranking and indexing. This shift has made site performance and security even more important.

Mobile users are often on slower connections and are particularly sensitive to security warnings. A site that loads slowly or triggers warnings on mobile is at a significant disadvantage.

HTTPS is also required for many mobile-specific features. Progressive Web Apps, which can significantly improve mobile user experience, require secure connections. AMP (Accelerated Mobile Pages), while less popular than before, also works best with HTTPS.

Core web vitals and page experience

In 2021, Google introduced Core Web Vitals as ranking factors—metrics that measure loading performance, interactivity, and visual stability. While HTTPS isn't directly part of Core Web Vitals, it's part of the broader "page experience" signals that Google considers.

Google's page experience documentation explicitly lists HTTPS as one of the components they evaluate. A page that scores well on Core Web Vitals but lacks HTTPS is still providing a suboptimal experience from Google's perspective.

The message is clear: Google wants the web to be fast, stable, and secure. SSL certificates address the security component of that equation.

The SEO risk of expired certificates

Here's something many SEO guides overlook: an expired SSL certificate can undo all your SEO efforts overnight.

When your certificate expires, browsers display full-page security warnings. Visitors bounce immediately. Your carefully optimized pages become effectively unreachable. And while Google doesn't instantly deindex sites with expired certificates, prolonged expiration can definitely impact your rankings.

Even a few hours of certificate expiration during a critical period—like a product launch or a seasonal sales peak—can have lasting effects on your SEO momentum.

Common concerns about HTTPS and SEO

Some website owners worry that migrating to HTTPS might hurt their SEO. These concerns are usually unfounded, but they're worth addressing.

The migration process does require some care. You need to set up proper 301 redirects from HTTP to HTTPS, update internal links, submit the HTTPS version of your site to Google Search Console, and update your sitemap. If done incorrectly, you might see temporary ranking fluctuations.

However, Google provides extensive documentation on HTTPS migration, and countless sites have made the switch successfully. The short-term effort is vastly outweighed by the long-term benefits.

Another concern is site speed. HTTPS does add some overhead due to the encryption process. However, modern implementations (particularly with HTTP/2, which requires HTTPS) can actually be faster than plain HTTP. The performance difference is negligible for well-configured sites.

The competitive landscape

Here's a practical reality: most of your competitors probably already use HTTPS. According to various studies, over 95% of pages loaded in Chrome use HTTPS. If you're in the minority still using HTTP, you're at a disadvantage.

In competitive markets, you can't afford to give up any advantage. When your competitors have SSL and you don't, you're not just missing out on a ranking boost—you're actively handicapping yourself.

Conclusion

SSL certificates are not a magic SEO solution, but they are an essential foundation. Google has made their preference clear, and the data supports the importance of HTTPS for search visibility.

If you haven't made the switch to HTTPS yet, you're leaving SEO value on the table. If you have, make sure your certificates stay valid—an expired certificate can undo all your good work.

In the world of SEO, every advantage counts. SSL is one of the easier advantages to secure.