The Hidden Cost of EKS Control Plane

AWS charges $0.10 per hour for an EKS cluster. That comes out to roughly $73/month.

For a business, that sounds like a rounding error. But it’s a trap.

The $73 is just the cover charge to get into the club. Once you’re inside, the drinks are expensive.

1. The NAT Gateway Tax

EKS nodes in private subnets need a NAT Gateway to talk to the internet (or even to AWS services if you don’t use VPC Endpoints). Cost: ~$32/month per AZ. For high availability (3 AZs), that’s $100/month—more than the cluster itself.

2. The Cross-AZ Traffic

Every time a pod in Zone A talks to a pod in Zone B, you pay $0.01/GB. In a chatty microservices architecture, this can easily be hundreds of dollars.

3. The Upgrade Treadmill

Kubernetes releases a new minor version every 4 months. AWS supports it for about 14 months. The cost of engineering time spent upgrading EKS versions, testing addons, and rotating nodes is the biggest line item of all.

Conclusion

Don’t budget $73 for EKS. Budget $500 + 10 engineering hours per month. If that math doesn’t work for your project, maybe a monolith on App Runner is a better choice.