What is a SAN [Subject Alternative Name] Certificate? [Detailed Guide]

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What is Multi-Domain SAN Certificate

SAN SSL certificates are the ideal solution for small, medium-sized, and multinational companies wanting to secure several websites with a single SSL certificate. A SAN certificate offers unlimited FREE reissues and protects over 200 FQDN domains or websites across several web servers.

Depending on the type and amount of validation, an SSL certificate’s average annual cost constantly changes. Like this, you will pay a significant amount each year if you own ten websites. That’s too much for website maintenance. Even if it is required, what if there was an alternative? Are you curious to find out?

The good news is that SAN SSL certificates provide an answer. Now, what is it, and what does it do? How can one be obtained? This essay will provide answers to each of these crucial questions! Let’s continue to explore.

What is a SAN Certificate?

What is a SAN Certificate?

A SAN certificate is also called Multi-Domain SSL certificate that can secure numerous domains or subject alternative names (SAN) under a single certificate, according to the discipline of cybersecurity. Anytime within the SAN certificate’s validity period, a user may alter the Certificate and add up to 250 subject names.

Additionally, the installation procedure and certificate administration are easier to handle.  You can secure services ActiveSync, POP3, IMAP4, Outlook Anywhere, Unified Messaging, etc. with a SAN or UCC certificate.

Do you know that all servers may not support installing multiple certificates?

Using a 128-256-bit encryption technique, the SAN SSL certificate can secure internal and external domain names. They are also known as “Unified Communications Certificates” as they were initially developed for Microsoft’s Exchange and Communications servers.

All you need to do is get a single SAN SSL certificate. To provide the best protection for all your domains, you can put them under it. Here are a few crucial details of SAN certificates.

What is the Use of a SAN SSL Certificate? 

It might be necessary to provide each website its unique IP address if you intend to host many SSL-enabled websites on a single server. Again, you may only secure the top-level sub-domains and the primary domain using a Wildcard certificate.

The Certificate with Subject Alternative Names could be beneficial and fit this use case well. By using a SAN Certificate, the administrator can avoid the headaches of setting up many IP addresses on the server and connecting them to various certificates.

How does SAN Work?

How does SAN Certificates Works?

Since it is so robust, you can install SAN SSL on an infinite number of servers. Additionally, the multidomain SAN certificate includes wildcard certificate characteristics if you are considering securing websites built on any of your sub-domains.

With a multi-domain wildcard certificate, you can protect an infinite number of first-level subdomains for any domain you choose. SAN is a single proficient certificate to secure all your domains and subdomains; this is where things come full circle.

Moreover, you can secure several websites with a single dedicated IP address with the help of SAN SSL certificates.

  • If the domain needs to change, it can be quickly renewed. There is no additional cost for doing this.
  • With many private keys, the SAN can be applied to unlimited IP addresses.
  • An infinite number of servers can be deployed and utilized with a SAN certificate.
  • Users can secure as many domains as possible under a single multidomain SSL certificate.

Below are some instances of multidomain.

  • www.example.com
  • example.com
  • example.net,
  • Anything.domain.com, etc.

The certificates can be used simultaneously with numerous servers, unlimited IP addresses, and multiple private keys. The number of entries is often unlimited; however, it will vary across the different CAs. No additional costs are associated with changing the domains covered by the Certificate at any time.

Where to Check your Certificate’s SAN Information

A multi-domain SSL certificate lets you know which additional domains are protected if you want to look while browsing a website that utilizes it. Choose certificate by selecting the padlock icon in your browser’s URL bar.

In the Show dropdown option under the Details tab, click Extensions Only.

Details Extensions Tab

To view the list of SANs, select Subject Alternative Name, the third option.

Subject Alternative Name

So that’s all. What, did you expect more? We can refer you to various certificate authorities (CAs) that are reliable in the industry, where you may get a SAN certificate.

Product NamePrice/yr
Comodo Multi-Domain SSL Certificate (Flex)$12.99
Sectigo Positive Multi-Domain SSL$32.99
GeoTrust QuickSSL Premium SAN$106.00
Comodo UCC SSL$115.99
Sectigo Multi-Domain SSL$126.99
View More SAN SSLs

Among all Certera Multidomain SSL Certificate is affordable and standard, effectively protecting several websites. Moreover, it can effectively secure subdomains if the sub-domains have been included in the list of subject alternative names (SANs) in the Certificate.

  • Every Multidomain SAN certificate from Certera Store has the following further advantages:
  • Secure and protect up to 250 fully qualified domain names (FQDNs)
  • Enjoy 256-bit encryption or higher.
  • Show a secure website indicator on your website, such as a secure padlock icon and HTTPS in the URL bar.
  • Utilize the FREE, round-the-clock assistance from expert technicians.
  • Get assured with a 30-day money-back guarantee and 99.99% Browser Trust.

Benefits of Multi-Domain (SAN) Certificates

Advanced Site Security

You want existing customers and new website visitors to browse your products and purchase online. However, how can you persuade people to feel secure about making transactions on your website?

By making your website secure and keeping users’ personal and financial information, you can improve their comfort level using the secure HTTPS protocol instead of the insecure HTTP protocol.

The critical distinction between the two is that an HTTPS-enabled website establishes an encrypted communication channel between the user’s web browser and server to transmit user data.

Potentially malicious third parties can intercept and “read” the data sent through an HTTP connection since it is being sent over an unprotected channel. Both you and your clients don’t want that. Simply put, it’s the distinction between speaking clearly on a secure connection and clearly on an unsecured one.

Level of Validation

A trustworthy certificate authority (CA) first validates the domain’s ownership and the legitimacy of the organization before issuing any multidomain SSL certificate. This procedure is referred to as validation. Domain validation (DV), Organisation validation (OV), and Extended validation (EV) are the several sorts of validation levels that are available with SAN certificates.

The CA validates that the individual or organization looking for the SAN certificate owns the registered domain as part of the domain validation process, which is a one-step procedure.

Unlike an organization validation SSL certificate, which goes further to confirm your company is legitimate by confirming your company’s name, physical location, and phone number, this is different. Extended validation SSL goes beyond the OV SSL verification procedure, making it the most reliable SAN SSL cert.

Strong Protection

With 256-bit encryption and 2048-bit CSR encryption, all domains and sub-domains will be well-protected. Between the server and the user, each byte will have high security. Information that is sent between two endpoints is untraceable to cybercriminals. Consequently, details are preserved, and people exchange information without being tracked.

Domain Coverage with Various TLDs

Organizations frequently purchase domain names with various TLDs to preserve their brand identity and profit from Google’s localized search results. It used to be extremely expensive and time-consuming to get individual SSL certificates for each domain that utilized a different TLD. Since SAN certificates allow for the inclusion of all domain names with various TLDs under a single SSL certificate, they are offered by almost all major certificate authorities (CAs).


The scalability of your company is considerably improved with SAN SSL certificates. It is a huge thing when you examine the entire Certificate issuing procedure because you no longer need to purchase and set up a new certificate on your server when creating a new website for your company.

It entails creating certificate signing requests (CSR), uploading them to the SSL certificate seller, and ordering and installing the Certificate. This scenario might take a lot of time, depending on how many websites you want to build (let’s say you want to build a micro-site for each item). With a SAN SSL certificate, you may add the names of your new websites to the existing SSL certificate without wasting time or money.

Exceptional Industry Savings

You would save money by purchasing only one SAN SSL certificate, another great benefit. A single SAN SSL certificate would be less expensive than a single domain certificate for each domain. Additionally, you will save considerable effort and time throughout the certificate management procedure.

Supported by All Major Browsers

All browsers, smartphones, and other devices are compatible with SAN SSL certificates. Therefore, SAN certificates give various website security options that combine the finest protection with effectiveness and efficiency. These reasonably priced certificates have hassle-free, outstanding service.

Unlimited Server Licenses

There is no need to be concerned about multiple installations because multidomain SSL certificates can be configured on several servers without additional fees. Features like unlimited server licenses might be helpful when distinct domains are split over several servers. This Certificate may secure all primary, secondary, and backup servers. In managing a load-balancing scenario, SAN SSL is also beneficial.


A SAN SSL certificate is a simple yet effective security solution for all your websites built on different domains and subdomains. You can even protect several domains on various TLDs for the price of only one SAN SSL certificate.

As a result, managing and applying a cost-effective SAN certificate to secure your website is a simple task that will shield your personal, company, and client information from unauthorized access.

Therefore, if you are convinced that a SAN SSL certificate would be the most appropriate for your objectives, order one immediately from Certera.com.


What is a SAN Certificate?

A SAN certificate is an SSL/TLS certificate that can secure several domains or subject alternative names (SAN) with a single certificate, according to cybersecurity. Users can alter the Certificate and add up to 250 topic names throughout the SAN certificate’s validity duration.

What is the Use of Subject Alternative Names?

SAN certificates are necessary for Exchange Servers, Office of Communications Server, and situations where several domains that resolve to a single IP address need to be protected (such as in a shared hosting environment).

What types of SAN certifications are there?

With SAN certificates, you can choose between domain validation (DV), organization validation (OV), and extended validation (EV).

How many domains can a SAN certificate secure?

A SAN certificate will protect one primary domain and the number of subdomain domains (also known as SANs) you designate. The maximum number of domains you can protect with a single certificate is 250.

What benefits do multidomain SSL certificates have over single-domain SSL certificates?

Because a multidomain SSL Certificate protects several domains under a single SSL and CSR, it can save the time and cost of SSL management. This implies the above speculation that you do not have to handle each domain individually.

Janki Mehta

Janki Mehta

Janki Mehta is a passionate Cyber-Security Enthusiast who keenly monitors the latest developments in the Web/Cyber Security industry. She puts her knowledge into practice and helps web users by arming them with the necessary security measures to stay safe in the digital world.