How do I change the hostnames that an SSL certificate works with?

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If we host your DNS (as we do for most customers), we usually provide a “wildcard” Let’s Encrypt SSL certificate that works for “example.com” and any subdomain immediately below that, including “www.example.com” and other names like “blog.example.com” and “shop.example.com” that you might use in subdomains.

(If we don’t host your DNS because you’ve added DNS entries elsewhere, you’ll need to use our control panel to order a non-wildcard certificate that contains only the hostnames you’ve pointed here.)

With a wildcard certificate, you won’t need to change anything to start using another hostname at the same level — for example, if you currently have a certificate working for “www.example.com”, you don’t need to do anything extra to make it work with for “blog.example.com”.

If you need to add more levels to a wildcard certificate (like adding “www.blog.example.com”) or add hostnames to a non-wildcard certificate, you’ll need to open a ticket and ask us to add them. We will obtain and install a new certificate for your site within one business day.

Limitations on reissuing certificates

The Let’s Encrypt project has a fixed limit on the number of certificate changes per week. Each time you ask us to add one or more hostnames, that counts as a change. Because of that, you should tell us all your additions at once, and we can only make one change per business day.

Maximum number of hostnames

We support up to 20 hostnames or wildcard entries per free certificate.