One VPC is global by default — unlike an AWS VPC or Azure VNet.
A single GCP VPC spans every region with no peering required to route between them, over Google's own private backbone.
One global VPC, subnets everywhere
us-central1
Zone a
Zone b
Zone c
europe-west1
Zone b
Zone c
asia-southeast1
Zone a
Zone b
A project is four boundaries at once
Billing
Links to exactly one Cloud Billing account at a time.
IAM
Policies attach here or above, applying to everything inside.
Quota
API calls, cores, and IPs are tracked per project.
API enablement
A service's API must be explicitly enabled here first.
AWS bundles isolation + billing into one account. GCP splits them: project (isolation) and Cloud Billing account (payment) — one billing account routinely pays for dozens of projects.