Yes, all new A2 Hosting accounts support Let's Encrypt.
Using an SSL certificate from a recognized Certificate Authority is recommended for best results when enabling SSL. Let’s Encrypt is a free, automated, and open Certificate Authority, and is recognized by most modern browsers. Let's Encrypt is supported for all new A2 Hosting accounts, and certificates may even be generated automatically for immediate use.
For more information regarding Let's Encrypt for your account type, please see the Related Articles section below.