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SSL certificates are an important part of securing your website, and often have additional benefits, such as better search engine rankings.
In this article, we'll provide a better understanding of a particular type of SSL certificate - the SAN certificate.
What Is a SAN/Multi-Domain SSL Certificate?
A SAN SSL certificate, sometimes referred to as a multi-domain or UCC certificate, allows multiple domains or subdomains to be secured with the same SSL certificate.
Subject Alternative Name (SAN) is an extension of the SSL certificate standard, allowing additional domains the be defined outside of the certificate's common name. By using the SAN extension within your SSL certificate, it can be re-issued to support additional domains, all with the same certificate and CSR.
In modern times, almost all SSL certificates issued are technically SAN certificates, although the ability to attach multiple domains to them will depend on the issuer. As a general rule, if you're buying an SSL certificate that is labeled as a "multi-domain" certificate, it's a SAN certificate.
Where To Get A SAN SSL Certificate
As we mentioned previously, almost all SSL certificates issued these days support SAN.
A few of the top providers that allow for multi-domain/SAN SSL certificates are:
While there is no technical limitation for the number of domains that can be attached to a SAN certificate, different SSL issuers may place restrictions or require additional fees for adding additional domains. If you have more than a few domains that you'll be adding to a certificate, be sure to check with your issuer for specifics.
Most of the time, additional domains will not need to be defined when generating your CSR, and the same CSR can be used when changing SAN hostnames. The issuers that we've listed above fall under that rule, but other issuers may have different rules.
When purchasing a SAN SSL certificate from an issuer that we haven't mentioned in this article, it might be a good idea to check with them to see if you'll need to define additional domains when generating a CSR.
Installing a SAN SSL Certificate
The installation of a SAN certificate can be done the same way as installing a single-domain certificate at Pagely.
For more information, see our article on installing 3rd-party SSL certificates.