SSL Certificate for Subdomains: Which Certificate Does Your Website Need?

Running a SaaS platform, client portal, or multi-store eCommerce setup? One unsecured subdomain is all it takes to break your site’s overall security and users’ trust. Choosing the right SSL Certificate for Subdomains checks that every part of your site is encrypted, trusted, and aligned with modern browser and SEO expectations.

Rather than managing separate SSLs for each subdomain, businesses are now opting for Wildcard SSL Certificates – a single solution that secures your primary domain and all its first-level subdomains at once.

In this blog, we’ll break down the types of SSL certificates available for subdomains, explain what each one covers, and help you decide which certificate your website needs.

What is SSL and Why is it Important for Subdomains?

SSL (Secure Socket Layer), also referred to as TLS (Transport Layer Security), is a security protocol that encrypts data transmitting between an internet server and a web browser. When a website uses SSL certificate, its URL starts with HTTPS – where ‘S’ stands for secure. It shows visitors that the site is secure and safe to interact with.

Modern browsers and search engines like Google prioritize HTTPS websites, and those without proper SSL protection are often flagged as “Not Secure”. Now, here’s where it gets important for growing websites: not every SSL certificate automatically protects subdomains.

Subdomains are extensions of your main domain used to organize content or services – for instance, support, blog, or checkout pages. It helps users understand the website structure based on its URL. If they’re not individually secured, they can be left open to risks, even if your main domain is protected.

Hence, choosing the right SSL for subdomains matters because every part of your site, not just the homepage, is covered by strong encryption.

Types of SSL Certificates for Subdomains

Several types of SSL certificates can be used to secure subdomains, each providing varied degrees of safety and verification. Choosing the right SSL for subdomain security depends on what kind of security and validation your organization needs. Below we have discussed three different types of SSL certificates, which are used to secure subdomains.

1. Wildcard SSL Certificate

   A Wildcard SSL Certificate is the best fit for securing one primary domain and its unlimited first-level subdomains. It makes SSL management easy as you do not need to list each subdomain individually.

   • Example: It can secure www.yourdomain.com, blog.yourdomain.com, store.yourdomain.com, login.yourdomain.com, and more as you scale.
   • Does Not Secure: These certificates cannot cover different domains e.g., yourdomain.net or second-level subdomains e.g., shop.us.yourdomain.com.
   • Validation Type: Available in Domain Validation and Organization Validation.
   • Cost Efficiency: Highly cost-effective for websites with many subdomains on the same root domain.
   • Use case: Ideal for businesses running multiple services like blogs, stores, or portals – under the same domain.

2. Multi-Domain SSL Certificate

   Also known as a SAN (Subject Alternative Name) certificate, this SSL can secure multiple domains and subdomains, provided each is listed as a SAN.

   • Example: It can secure www.yourdomain.com, blog.yourdomain.com, yourdomain.net, and even shop.us.yourdomain.com.
   • Subdomain Coverage: Each subdomain must be listed separately in the certificate’s SAN field as wildcard coverage is not supported.
   • Validation Type: Comes with DV, OV, and EV Validation levels.
   • Flexibility: Businesses managing multiple domains like brand1.com, brand2.com, and subdomains such as app.brand1.com, all secured under one certificate.

3. Multi-Domain Wildcard SSL Certificate

   A Multi-Domain Wildcard SSL Certificate is a good option for organizations managing multiple subdomains. It combines the flexibility of wildcard coverage without the need for multiple individual certificates.

   • Example: Secures *.example.com, covering blog.example.com, store.example.com, and support.example.com.
   • Maximum Coverage: Supports unlimited first-level subdomains under a single certificate.
   • Validation Type: Generally available in DV and OV types.
   • Benefit: Saves time, reduces cost, and simplifies SSL management for large setups with several web properties.
   • Use case: Perfect for a parent company or holding group managing different brands or departments.

How to Obtain an SSL Certificate for Subdomains?

The general steps to obtain an SSL certificate for subdomains are:

1. Select Appropriate Certificate Type: Decide if you want to purchase a Wildcard SSL, Multi-Domain SSL or a Multi-domain Wildcard certificate. Choose a certificate which aligns with your organization’s needs.
2. Select an SSL Certificate Provider: Look for a provider like CheapSSLShop offering top brands at discounted rates and 24/7 support.
3. Make a Certificate Signing Request: CSR is created on your server and contains encrypted information about your domain. Don’t worry, most hosting dashboards have built-in tools to do this.
4. Give CSR to Provider: Share the CSR with your provider and complete the required domain or business verification steps.
5. Put the SSL Certificate in Place: After the certificate is issued, upload it on your server. Usually, your hosting provider or SSL support team will help you in this process.

Benefits of Securing Your Subdomains with SSL

Securing your subdomains with an SSL certificate is a smart move for your security, SEO, and reputation. Here’s why:

• Improved Security: SSL encrypts data between browser and server, so your login details, transactions, and form submissions are safe from hackers.
• Enhanced User Trust: An SSL certificate activates the “https” in a URL, indicating a safe connection to website visitors.
• Improved SEO Ranking: Search engines give preference to websites using SSL certificates, which ultimately results in better positions on SERPs.
• Regulatory Compliance: SSL helps meet data protection standards like GDPR, HIPAA, and PCI-DSS, especially when subdomains handle sensitive info.
• Unlimited Subdomains: Wildcard SSL protects unlimited first level subdomains with a single certificate.
• Cost-Effectiveness: Managing one SSL by using one Wildcard or Multi-Domain SSL certificate is more affordable and far easier than handling separate certificates for each one.

Best SSL Certificates for Subdomains in 2025

If you’re looking to secure subdomains in a scalable and affordable way, these SSL certificates offer some of the best value in 2025—trusted encryption, broad compatibility, and strong warranties.

1. Sectigo Wildcard SSL Certificate

   Secure your main domain and unlimited first-level subdomains with strong encryption and ECC support. Ideal for blogs, portals, and sub-services under one domain.

   • Domain Validation
   • $500,000 Warranty
   • Priced at $65.00/year
   • Includes dynamic site seal

   Buy Sectigo DV WildcardSSL Certificate Now

2. PositiveSSL Multi-Domain Wildcard

   Best for businesses managing multiple domains with subdomains. Covers multiple wildcard domains like *.example.com, *.example.net, and more.

   • Domain Validation
   • $10,000 Warranty
   • Priced at $80.00/year
   • Use Case: Scalable for SaaS platforms, agencies, or enterprise sites

   Buy PositiveSSL DV Multi-Domain Wildcard Certificate Now

3. PositiveSSL Multi-Domain

   A flexible, budget-friendly choice to secure several domains or subdomains under different TLDs (e.g., .com, .net, .org). Each must be listed separately.

   • Domain Validation
   • $10,000 Warranty
   • Only $15.00/year
   • Use Case: Startups or small businesses with multiple web properties

   Buy PositiveSSL DV Multi-Domain Certificate Now

4. Sectigo OV Wildcard SSL

   Ideal for growing businesses that want stronger authentication. Secures unlimited subdomains and displays verified organization details in the certificate.

   • Organization Validation
   • $1,000,000 Warranty
   • Priced at $90.00/year
   • Use Case: E-commerce, fintech, or portals needing higher trust

   Buy Sectigo OV Wildcard SSL Certificate Now

FAQs: SSL for Subdomains

Should I get a unique SSL certificate for every subdomain?

Instead of buying seperate certificates for every subdomain, you can use a Wildcard SSL, Multi-Domain SSL, or Multi-Domain Wildcard SSL. This way you can secure multiple subdomains and even domains with a single SSL, saving time, money, and administrative hassle.

Can I protect all subdomains as well as my main domain using a single SSL certificate?

With a Wildcard SSL certificate, your main domain and all the first level subdomains linked to it can be secured. But it will not cover deeper nested subdomains.

How may I set up a wildcard SSL certificate?

A Wildcard SSL certificate’s installation process is similar to standard SSL certificate. You’ll need to:

1. Generate a Certificate Signing Request on your server using *.example.com as the common name.
2. Submit the CSR to your SSL provider and complete domain validation.
3. Install the issued certificate on your hosting server.

The exact steps may vary depending on your hosting panel or server type.

Conclusion

Protecting your subdomains with the right SSL certificate for security, trust, and SEO is non-negotiable. Whether you choose a Wildcard, Multi-Domain, or Multi-Domain Wildcard SSL, make sure it aligns with your site’s structure and growth plans.

Get affordable, trusted SSL certificates for subdomains at CheapSSLShop.

Related Posts:

• What is a Double Wildcard SSL Certificate? How it Differs from a Standard Wildcard SSL?
• Standard SSL vs. Wildcard SSL Certificates: Which One to Choose for Your Website?
• Where to Buy Wildcard SSL Certificate: A Quick Guide
• Top 5 Best Cheapest Wildcard SSL Certificate Providers of 2025