This article outlines what operations in Terra have a GCP cost and how you will pay for GCP charges with a Terra billing project. It also explains the billing structure (i.e. GCP and Terra), how GCP calculates and bills Terra users for charges, and how Terra Billing projects act as a pass-through to pay for the GCP costs of your work in Terra. 

Contents

GCP fees in Terra 
The GCP/Terra billing structure in a nutshell
What does access to billing resources allow you to do? and not do? 
Billing roles versus workspace permission examples
Terra Billing projects versus Google Projects
Billing permissions FAQs
Additional resources (i.e. finding/estimating analysis costs in Terra)
 

GCP fees in Terra 

The Terra platform is free to use; you can browse showcase workspaces and the Data Library free as soon as you register for an account. There are no fees for contacting or working with the Terra support team. However, there are GCP costs associated with operations in Terra such as:

• Storing data in workspace buckets (see GCP storage pricing)
• Running workflows (see GCP compute pricing)
• Running interactive analyses - Jupyter Notebooks; Galaxy; RStudio (see GCP compute and GCP disk rates)
  
• Accessing data in Requester Pays buckets (see GCP egress pricing)

Terra passes along GCP charges with no markup through a Terra Billing project (note the links above will take you directly to the GCP pricing pages). 

The Terra/GCP billing structure in a nutshell

There are three levels to the cost structure in Terra. Each has its own function, and users/collaborators can be included with different permissions at each level in order to do different things.

At the top is a GCP Billing account, which is what you will ultimately use to pay GCP for storage, compute, and egress costs. At the bottom is a project workspace, where you actually store and move data or run an analysis. In between is a Terra Billing project, a pass through between GCP and Terra (in the diagram below, blue boxes are GCP components and gray are Terra components).

GCP costs are calculated per workspace, not per user!

Each workspace has a unique GCP Project that is automatically generated when you create the workspace. All these Google Projects (one for each workspace) are under an umbrella Terra billing project, which acts as a pass-through that pays the GCP costs from the GCP Billing account at the top of everything. For GCP accounting, it doesn't matter who does the work, it only matters how much data storage, egressing or analysis is done in the workspace. Think of your workspace like a car. The cost to fill the car with gas depends on how far the car has gone since the last fillup, not on who has been driving. If you give your colleague (or child) the keys to the car, they can accrue charges that you - the car owner - will be responsible for paying.

For example, the workspace below stores data for the Analysis, Visualization, and Informatics Lab-Space (AnVIL). The GCP storage fees are paid by the Google Cloud Billing account associated with the Terra Billing project anvil-datastorage (highlighted).

What does access to billing resources allow you to do (and not do)?

Terra's billing structure means that it is workspace permissions, not billing permissions, that directly control who can accrue costs on a Terra billing project.

Collaborators with billing access can create resources and then use them

Owners of Cloud Billing accounts and Terra Billing projects control who can create Billing projects and workspaces (respectively) by assigning the appropriate permissions (see the chart below). 

Collaborator costs
Note that anyone who creates a workspace is the owner by default, and can spend in the workspace they create. Thus a collaborator on a shared Billing project can create a workspace where they can accrue costs for storing and analyzing data. These costs will then be covered by the Terra Billing project, even if the collaborator is later removed from the billing!

Regardless of the user's billing status, workspace costs will be passed through to the Terra Billing project as long as the billing project is active.

Collaborators with workspace access can accrue costs in a workspace

A colleague does not need to be included in a Terra Billing project or a GCP Billing account to be able to work in Terra. They only need to have the appropriate ("can-compute") workspace permissions. To learn more, see Managing shared resources (billing, data, and workspaces. 

	Be mindful how you share workspaces!
	It is workspace permissions, not billing permissions, that allow you to accrue costs (directly) in Terra. This means if you share a workspace with someone as "Writer" or "Owner" they will be able to accrue costs by storing data or running an analysis, even if they are not a user of the workspace Billing project. To learn more about controlling cloud costs in Terra, see this article.

Example 1: Billing roles versus workspace permissions and accruing cost

Consider the case of four users collaborating in a workspace. Each has different different Billing project/workspace permissions (from left):

Which of these users can do work in the workspace? (click for answer)

All but the Workspace reader (third from left) can accrue cost by storing data or running an analysis in the workspace. The Workspace reader does not have the right workspace permission, even though they are a user on the Billing project.

Can colleagues who aren't in the Billing project work in a workspace?
Yes! That is because the Billing project funding the workspace covers work no matter who does it - as long as they have the right workspace permissions.

Example 2: Billing roles versus workspace permissions - Creating resources

Now consider these four users of a workspace funded by Terra Billing project A (from left):

Who can make their own copy of the workspace? (click for answer)

To make your own copy of a workspace to work in, you need to 1) have access to a Terra Billing project and 2) have "share" permission in the original workspace. Note that all Terra users have permission to make clones of "public" workspaces. 

Terra Billing projects versus Google Projects

Billing permissions FAQs 

Below are three examples - and what happens in each case - to help clarify the structure of billing in Terra.  

Additional resources

See these additional support articles about controlling costs on Terra: 

• Cloud costs and how to control them when working on Terra
• How much did my workflow cost?
• To learn more about estimating the cost of an interactive analysis - see Understanding and adjusting your Cloud Environment.