Hi, thanskf for your question. The statement "You can have up to 100 email aliases per domain." means that you can have up to 100 aliases as email addresses for the same Google account, for example, I can set help@xyz.com as an alias of john@xyz.com without paying extra for a new Google Workspace user license. But you can have unlimited users in the same Google Workspace, and there is no limit as far as I know. You just need to pay Google for each added user in your Workspace organization. There is a difference between "user" and "alias". Basically our Tier 3 license gives you unlimited user licenses in your Google Workspace. I hope this explains!