SSL Wildcard: The Complete Guide to Securing Multiple Subdomains

August 26, 2025 at 16:07 PM EDT

If you own a website with multiple subdomains, managing security can quickly become complex. Imagine having to buy and install a separate SSL certificate for each subdomain—it’s expensive, time-consuming, and difficult to maintain. That’s where an SSL Wildcard certificate comes in.

An SSL Wildcard certificate allows you to secure your main domain and all its unlimited subdomains with just one certificate. For businesses with growing digital ecosystems, it’s the smartest way to ensure robust online security while saving time and money.

In this article, we’ll explore what SSL Wildcard certificates are, how they work, their benefits, cost, and why they might be the right choice for your website.

What is an SSL Wildcard Certificate?

An SSL Wildcard certificate is a special type of SSL/TLS certificate that secures a primary domain (e.g., example.com) and an unlimited number of subdomains (e.g., mail.example.com, shop.example.com, blog.example.com).

Instead of purchasing multiple SSL certificates for each subdomain, you only need one SSL Wildcard certificate. This makes it a cost-effective and flexible security solution for businesses with multiple services or platforms under the same domain.

How Does an SSL Wildcard Work?

Wildcard certificates use a wildcard character (*) in the domain name field. For example:

Common Name: *.example.com
Secures: mail.example.com, blog.example.com, store.example.com

This means that any subdomain under example.com will automatically be secured without needing a new certificate.

However, it does not cover multiple levels of subdomains. For example:

Secured: store.example.com
Not secured: sales.shop.example.com

For that, you would need a multi-domain SSL certificate or a multi-domain wildcard SSL.

Why Choose an SSL Wildcard Certificate?

Cost-Effective Solution
- Instead of buying multiple SSL certificates, one SSL Wildcard certificate secures unlimited subdomains.
Easy Management
- You only manage and renew one certificate, simplifying security administration.
Scalability
- If you create new subdomains in the future, they’re automatically secured without extra steps.
Strong Encryption
- Provides 256-bit encryption and authentication for data security.
Improved SEO Rankings
- Search engines favor secure websites with HTTPS across all subdomains.
Customer Trust
- The padlock symbol builds confidence in your brand’s commitment to security.

Types of SSL Wildcard Certificates

Not all Wildcard SSL certificates are the same. They come in different validation levels:

Domain Validated (DV) Wildcard SSL

Quick and easy issuance
Only verifies domain ownership
Best for blogs, portfolios, or small websites

Organization Validated (OV) Wildcard SSL

Verifies business identity in addition to domain ownership
Provides stronger trust and credibility
Suitable for small to medium-sized businesses

Extended Validation (EV) Wildcard SSL

Rarely offered, as most EV certificates don’t support wildcards
For businesses that want maximum trust and credibility

Cost of an SSL Wildcard Certificate

The cost of SSL Wildcard certificates depends on the validation type and provider.

DV Wildcard SSL: $50 – $150 per year
OV Wildcard SSL: $150 – $400 per year
Premium Providers (DigiCert, GlobalSign, Comodo/Sectigo): $250 – $600+ per year

Free SSL providers like Let’s Encrypt do not support wildcard certificates unless configured with DNS-01 validation, and even then, they lack warranties and long-term reliability.

When Should You Use an SSL Wildcard?

An SSL Wildcard certificate is ideal if:

You run multiple subdomains (e.g., store, blog, support, app).
You expect to add new subdomains in the future.
You want to simplify SSL management and reduce costs.
You operate an e-commerce or business website that needs trust across all subdomains.

Steps to Get an SSL Wildcard Certificate

Choose a Trusted Certificate Authority (CA)
- Examples: DigiCert, Comodo (Sectigo), GeoTrust, RapidSSL, GlobalSign.
Generate a CSR (Certificate Signing Request)
- Use *.yourdomain.com when creating the CSR.
Complete Validation
- DV requires email/DNS validation
- OV requires business document verification
Receive and Install the Certificate
- Install it on your web server or hosting provider.
Update All Links to HTTPS
- Ensure all subdomains load securely with HTTPS.

Advantages of Using SSL Wildcard Certificates

Protects unlimited subdomains with one certificate
Saves money on multiple SSL purchases
Reduces complexity of certificate renewals
Enhances user trust with HTTPS everywhere
Works with most major browsers and devices
Provides strong encryption for sensitive transactions

Limitations of SSL Wildcard Certificates

While SSL Wildcards are powerful, they do have some limitations:

Do not cover multiple levels of subdomains (sales.shop.example.com)
If compromised, all subdomains are affected
Typically not available with Extended Validation (EV)

For businesses needing multi-level protection, a multi-domain SSL certificate or multi-domain wildcard SSL may be better.

FAQs About SSL Wildcard Certificates

Can I use one Wildcard SSL for multiple domains?
No. Wildcard SSL only secures subdomains of one primary domain. For multiple domains, choose a multi-domain SSL.
Does an SSL Wildcard affect website speed?
No. Modern SSL/TLS encryption is optimized and does not noticeably slow down performance.
How many subdomains can a Wildcard SSL secure?
Unlimited subdomains under a single primary domain.
How long does it take to issue a Wildcard SSL?

DV Wildcard: Minutes to hours
OV Wildcard: 1–3 business days

Can I upgrade from DV to OV later?
Yes, you can purchase a higher-validation certificate when needed.

For more helpful blog posts like this one, visit the rest of our site, YearlyMagazine.

Conclusion

An SSL Wildcard certificate is the ultimate solution for securing multiple subdomains under one domain. It offers cost savings, simplified management, scalability, and strong encryption, making it a smart investment for businesses with complex digital infrastructures.

By choosing the right SSL Wildcard, you can: