It is used to define who pays for a given set of Google Cloud resources and is connected to a Google payments profile

Billing account includes one or more billing contracts defined on the Payments profile Billing account can have sub-accounts for resellers, so you can bill resources to be paid by your customers

IAM roles can be applied at the organization level, billing account level and/ or the project level

Cloud Billing AccountPayments Profile
Cloud level resource managed in Cloud ConsoleGoogle level resource
Tracks all of the costs incurred by GCP usageTracks cost across ALL of our google services (Google Ads, Fi phone service, etc.)
A billing account can be linked to one or more projectProcesses payments for ALL Google services
A single invoice is created per Billing AccountStores information like name, address, etc. of who is responsible for the profile
Defines who pays for a given set of resourcesStores the various payment instruments (credit cards, debit cards, etc.) used throughout Google in the past
Connected to Payments Profile which includes a payment instrument, defining how you pay for the chargesAllows to view all the invoices, payment history, etc.
Has billing specific roles and permissions (established by IAM roles)Controls who can view and receive invoices for the various Billing Accounts and products

Billing Account Types

Self Serve (Online) Account
Payment instrument is a credit or debit card or its equivalent depending on the country/ region
Costs are charged automatically to the payment instrument
Supports Monthly And Threshold Billing (Charge cycle is automatically assigned and cannot be changed)

Invoice (Offline) Account
Payment instrument can be cheque or wire transfer
Invoices are sent by mail or electronically (Generally once a month)
We must be eligible for invoice billing

Payment Profile Types

Individual
Using your account for your own personal payment
Only we can manage the profile, we can’t add or remove users or change permissions on the profile

Business
Paying on behalf of a business, organization, partnership or educational institution
Payment Center is used to make payment from across Google Product offerings
Can add other users into the payment profile