• Wednesday, February 25, 2026

Knowledge Base

SSL for Subdomains

Securing Subdomains with SSL

How to get SSL certificates for your subdomains.

Automatic Coverage

When requesting Let's Encrypt, you can include subdomains:

  • example.com
  • www.example.com
  • blog.example.com
  • shop.example.com

Adding Subdomains to Certificate

  1. Go to SSL Certificates in DirectAdmin
  2. Edit your Let's Encrypt certificate
  3. Add subdomains to the list
  4. Request new certificate

Separate Certificates

Each subdomain can have its own certificate if needed.

Wildcard Certificates

Wildcard (*.example.com) covers all subdomains:

  • Let's Encrypt supports wildcards
  • Requires DNS validation
  • Covers unlimited subdomains

Common Subdomain SSL Issues

  • Subdomain not included: Add to certificate
  • DNS not pointing: Update A record
  • Wrong certificate shown: Check certificate order

Best Practice

Request a single certificate covering your main domain and all subdomains you use.