Tenants are logical entities (such as an individual, company or organization) that group together Splashback resources (such as Pools and Users).
When you sign up for a new Splashback account, you are automatically provisioned a new Tenant. Tenants are free of charge, and their use is highly encouraged to simplify User Permissions and their usage.
Every Pool and User belongs to a Tenant, and are known as Members.
External users (e.g. contractors and consultants) should not be added as Tenant Members, and should instead sign-up for their own Splashback account and Tenant. You can then create relevant User Permissions to grant them access to your data. The external user will not be charged unless they provision their own Splashback resources.