Should you use Amazon ECS or Amazon EKS?
Amazon ECS is AWS’s own container orchestrator: it has no charge for orchestration and fewer concepts to learn, but its API exists only on AWS. Amazon EKS is managed, conformant Kubernetes: it costs $0.10 per cluster-hour as of November 2026 and brings the Kubernetes API, Helm charts, operators and portability to other environments. Choose ECS for a simple, AWS-only container setup, and EKS when you need the Kubernetes ecosystem or expect to run outside AWS.
The difference in one table
| Amazon ECS | Amazon EKS | |
|---|---|---|
| Orchestrator | AWS-proprietary scheduler and API | Upstream Kubernetes, certified conformant |
| Orchestration fee | No additional charge | $0.10 per cluster-hour, $0.60 on extended version support |
| Units | Task definitions, tasks, services | Pods, Deployments, Services and the rest of the Kubernetes API |
| Compute options | Fargate, EC2, ECS Managed Instances, ECS Anywhere | Fargate, EC2 node groups, EKS Auto Mode, EKS Hybrid Nodes |
| Workload permissions | IAM roles assigned to tasks | IAM roles mapped to Kubernetes service accounts, plus Kubernetes RBAC |
| Configuration tools | Console, CLI, CloudFormation, CDK, Terraform | All of those, plus kubectl, Helm, Kustomize and GitOps tools |
| Version upgrades | None; AWS evolves the service | A Kubernetes minor version upgrade about three times a year |
| Runs outside AWS | ECS Anywhere registers external machines to an AWS-hosted control plane | EKS Hybrid Nodes and EKS Anywhere; the same manifests run on any conformant Kubernetes |
Cost
ECS adds no orchestration fee on Fargate or EC2; you pay for compute, storage and networking. ECS Managed Instances add a per-instance management fee on top of EC2, and ECS Anywhere costs $0.01025 per registered on-premises instance-hour.
EKS adds $0.10 per cluster-hour, about $73 a month per cluster. A cluster still on a Kubernetes version 14 months after EKS released it moves to extended support at $0.60 per cluster-hour, about $438 a month, unless you upgrade or disable extended support, as described in the EKS version lifecycle. EKS Auto Mode adds a per-instance management charge on top of EC2.
For one or two clusters the EKS fee is small next to compute. For teams with many small clusters, it adds up. The full breakdown is in how much managed Kubernetes costs.
Fargate works the same way under both: you pay for the vCPU, memory and storage a task or Pod requests. The AWS Fargate pricing guide compares it with EC2.
Operations
ECS has fewer moving parts. There is no cluster version to upgrade, no add-ons such as a network plugin or DNS to keep compatible, and AWS integrates load balancing, service discovery and secrets directly into task definitions.
EKS gives you a Kubernetes control plane run by AWS, but you still upgrade it. Each minor version removes deprecated APIs, so every upgrade needs a check of manifests, Helm charts and add-ons. Managed node groups and EKS Auto Mode reduce the node work; Auto Mode replaces nodes after at most 21 days and keeps them patched.
Ecosystem and portability
The main reason to accept the EKS overhead is the Kubernetes API. Open source software for databases, queues, observability, machine learning and CI usually ships as Helm charts or operators for Kubernetes. On ECS you translate those into task definitions yourself, or run the managed AWS equivalent.
Portability follows from the same API. A workload described in standard Kubernetes manifests runs on GKE, AKS, other conformant services or your own servers with changes limited to cloud-specific parts such as load balancer annotations, storage classes and identity bindings. An ECS task definition runs only on ECS. See what managed Kubernetes is for what conformance guarantees, and how to avoid cloud vendor lock-in for the wider picture.
When teams outgrow ECS
Teams usually move from ECS to Kubernetes for one of these reasons:
- They want to run open source software that is packaged as operators or Helm charts.
- They need clusters outside AWS: another cloud, on-premises hardware or edge sites.
- They need scheduling tools that exist as Kubernetes projects, such as batch job queues, event-driven autoscalers or GPU sharing.
- They hire engineers who already know Kubernetes and its tools.
If none apply, ECS is a sound long-term choice and not a stepping stone.
Migration cost in either direction
Container images move unchanged. What has to be rewritten:
- ECS to EKS: task definitions become Deployments and Services, IAM task roles become service-account role mappings, and AWS-native service discovery and load balancer settings become Kubernetes Services, Ingress or Gateway resources. Teams also add the Kubernetes tooling they did not need before: Helm, an ingress or Gateway controller and monitoring.
- EKS to ECS: the reverse, plus replacing any Helm charts and operators with ECS tasks or managed AWS services.
The effort scales with the number of services and with how much AWS-specific configuration each one carries.
Kubernetes beyond one cloud with Cloudfleet
Cloudfleet Kubernetes Engine is a CNCF-conformant managed Kubernetes service whose clusters can include nodes in AWS, other clouds and your own data centers at the same time. That keeps the portability argument for Kubernetes without tying the control plane to one provider; see what Cloudfleet is.