GCP load balancer cost: forwarding rules and data processing

Quick answer

GCP load balancers bill mainly by forwarding rules (first five ~$0.025/hour each, ~$18/month) plus data processed (~$0.008-0.01/GB). Rules bill whether traffic flows or not, so the cost shows up as load-balancer sprawl. Consolidate services behind one load balancer with URL maps and host/path routing, and put a CDN in front to offload data processing.

GCP load balancing is inexpensive per unit but easy to multiply. The bill is two parts — forwarding-rule hours and data processed — and the part that surprises people is the rule hours, which accrue on every load balancer whether or not it's busy.

The two charges

Forwarding rules: the first five are ~$0.025/hour each (~$18/month), additional rules cheaper. Charged continuously per rule.
Data processed: ~$0.008-0.01/GB through the load balancer. Scales with traffic.

At low traffic the rule hours dominate; at high traffic, data processing does. There's no large fixed platform fee beyond the rules.

The sprawl problem

Because each forwarding rule bills ~$18/month standing, a project that spins up a load balancer per service or per environment racks up rule charges for capacity that's mostly idle. The fix is the same as on AWS (ALB/NLB) and Azure: route many services through one load balancer using URL maps and host/path rules instead of one balancer each, and delete the ones left over from torn-down stacks.

Offload data processing with a CDN

For content-serving workloads, putting Cloud CDN in front means cached responses are served from the edge and never hit the load balancer's data-processing meter. The more repeat, cacheable traffic you serve, the more this cuts the per-GB portion — the same caching logic as GCP egress.

FAQ

How is a GCP load balancer priced?

Mainly by forwarding rules and data processed. The first five forwarding rules cost ~$0.025/hour each (~$18/month per rule), additional rules less, plus ~$0.008-0.01/GB of data processed through the load balancer. There's no large fixed platform fee — the forwarding-rule hours are the base cost.

Why am I paying for a GCP load balancer with little traffic?

The forwarding-rule charge applies whether or not traffic flows — about $18/month per rule for the first five. A project with many load balancers (one per service or environment) accumulates these hourly charges. Consolidating with URL maps and host/path routing on a single load balancer reduces the rule count.

What's the difference between global and regional load balancer cost?

Global load balancers (for global HTTP(S), with a single anycast IP) and regional load balancers price similarly on forwarding rules and data, but global adds the benefit of one IP across regions. The cost driver is the same — rules plus data processed — so the choice is about architecture, not a big price gap.

Does data processing dominate the load balancer bill?

At high traffic, yes. The per-GB data-processing charge scales with throughput, so a high-traffic load balancer pays mostly for processing while a low-traffic one pays mostly for forwarding-rule hours. Knowing which dominates tells you whether to consolidate rules or optimize traffic.

How do I reduce GCP load balancer costs?

Consolidate services behind one load balancer using URL maps and host/path routing instead of one per service, delete load balancers from torn-down environments, put a CDN in front to offload data processing for cacheable content, and avoid creating extra forwarding rules you don't need.

How does C3X estimate load balancer cost?

C3X prices the load-balancer forwarding rules and related Compute Engine networking resources from your Terraform and treats data processed as usage-driven, so the base rule cost is visible before deployment.

What to do next

The forwarding-rule cost is fixed and easy to forget across many environments. C3X prices your load-balancer rules and related Compute Engine networking from your Terraform and models data processed as usage, so load-balancer sprawl surfaces before it adds up. The quickstart runs it in minutes.