NAT and gateways

Cloud NAT lets instances without external IP addresses reach the internet, and bills for every gigabyte that passes through it, inbound as well as outbound. That is the detail that surprises people: downloads are charged too, and the NAT charge stacks on top of internet egress for outbound traffic.

Billed: Per gibibyte processed through the NAT gateway, in BOTH directions, plus an hourly charge per gateway.