An artist's rendering of a company's reputation.
The free ride is over for early users of the company's custom domain G Suite service. For the first six years of the service's existence, the basic tier allowed you to create a custom domain account for free. You have to pay for the privilege of using a custom domain. In 2012 the ability to create these accounts for free was turned off, but it wouldn't take away accounts from existing users.
If the account holder doesn't switch to a paid account, the free G Suite accounts will be shut down. The users of the "G Suite legacy free edition" have until July 1 to start paying. There is a support page for this process. If it has billing information, it will try to upgrade users to a paid account. Accounts will be suspended if there is no information by July. After 60 days, those accounts will no longer have access to "core" services.
In 2006 the custom domain was called "google apps for your domain." The setup has always been the same, even though the service has had a bunch of name changes since then. The service starts at $6 per user, per month, with higher tiers available for higher storage needs. The basic tier was free from 2006 to 2012
The billing section of admin.google.com will show you what kind of G Suite account you have.
These users did nothing wrong when they signed up for G's basic tier years ago, so seeing them left out is rough. You assume that the basic terms of your account will be the same forever because you trust the company to store all your data. These people are being told that they need to start paying or lose their account.
If you don't want to pay for an account under a consumer account, rebuilding an account under a consumer account is a lot of work. There's no way to export things like content purchases for books, movies, music, and apps from these accounts. You will probably lose your phone number. If you used your G Suite account like this, you only have to start paying. It would have been great to offer users an easy way to port their data to a free account with a new email address. That isn't happening.
If you're confused about the status of your business account, you can go to the "Billing" page of admin.google.com. An email will be sent soon detailing how you will be hit by the change Suite if you see a message about being on a "G legacy" account. If you got your account through a bundled service like a domain hosting site, you'll want to check it out.