An intermediate certificate plays a crucial role in website security, helping browsers verify that a website’s SSL/TLS certificate can be trusted. It acts like a middleman between your website’s certificate and a root certificate from a trusted certificate authority (CA). Without it, your site might throw security warnings even if you have a valid certificate installed. So, understanding how it fits into the chain of trust is important if you’re managing or launching a website.

How an intermediate certificate fits into the chain of trust

In SSL/TLS encryption, trust comes from a certificate chain that connects your site’s certificate to a root certificate. The intermediate certificate sits between these two. It’s issued by a trusted CA and used to sign your server’s certificate, proving its legitimacy.

This layered approach protects the root certificate from being compromised. Instead of issuing certificates directly from a root, CAs use intermediate certificates to maintain security. When someone visits your site, their browser checks this chain to ensure the certificate is valid and comes from a trusted source.

Why intermediate certificates matter for SEO and user trust

Search engines take website security seriously, and using a valid certificate chain—including intermediate certificates—can improve your SEO performance. Google, for example, uses HTTPS as a ranking factor, so any errors in your SSL setup might hurt your rankings.

Plus, users are more likely to trust your site if it doesn’t display scary browser warnings. A missing or misconfigured intermediate certificate can result in trust issues that push visitors away. So, getting it right isn't just technical—it's also about building a good experience.

Installing intermediate certificates correctly

When you purchase an SSL certificate from a provider, they often supply one or more intermediate certificates with it. During installation on your server, it’s essential to include the full certificate chain. If you skip this, your site may appear broken or untrustworthy to some users or browsers.

Some platforms and website builders handle this process for you, but if you're managing your own hosting or using a custom server, double-checking the chain is a must. Make sure to test your setup using SSL tools that verify if all necessary certificates are in place.

Troubleshooting common issues with intermediate certificates

One common issue is the “untrusted certificate” warning, which usually means the intermediate certificate wasn’t properly installed. Another problem is browser compatibility—some older browsers might not recognize newer intermediate certificates unless your server is configured properly.

To fix these problems, you can re-check the certificate chain, download the correct intermediate files from your CA, and re-install them in the correct order. Using tools like SSL Labs’ SSL Test can help identify what’s missing or misconfigured.

FAQs about intermediate certificate

What is the difference between a root and an intermediate certificate?

A root certificate is issued by a certificate authority and is embedded in browsers and operating systems. An intermediate certificate is issued by the root and used to sign server certificates, creating a secure trust chain. Intermediate certificates reduce the risk of compromising the root by adding a buffer layer.

What happens if an intermediate certificate is missing?

If it's missing, browsers may not trust your website’s certificate—even if it’s technically valid. Visitors may see security warnings or be blocked from accessing the site entirely. Always ensure that the full certificate chain is installed on your server.

How do I know if my site is using the correct intermediate certificate?

You can use tools like SSL Labs' SSL Test or your hosting provider’s diagnostics to check the full certificate chain. These tools will tell you if anything’s missing or improperly configured, helping you correct any issues before visitors notice.

Can I install an intermediate certificate manually?

Yes, especially if you're using a self-managed hosting environment. You’ll usually get a .crt or .pem file from your certificate provider that you need to upload and configure on your server. Make sure to follow your hosting provider’s steps for chaining certificates properly.

Is an intermediate certificate included in all SSL certificates?

Most commercial SSL certificates come with the required intermediate certificates. However, it’s your responsibility to ensure they’re installed. Some platforms automate this, but if you’re doing it manually, always double-check the certificate chain to avoid trust issues.

Build trust into your site from the start

Having a secure certificate chain, including the right intermediate certificate, isn’t just a backend concern—it directly impacts your credibility and visibility online. Whether you're launching a new blog, building out a website, or fine-tuning your SEO, don't overlook this critical detail.

B12’s AI website builder handles SSL setup for you, so you can focus on growing your business instead of troubleshooting certificate errors. Get started today and launch a trustworthy site with ease.