If you are running containers on AWS, you need a secure place to store and share your images. Amazon ECR offers a managed registry that handles image storage, scanning, permissions, and versioning without extra configurations.
In this guide, you’ll learn what Amazon ECR is, how it works, its features, real-world benefits, and pricing. We will also introduce you to a cost intelligence approach to keeping ECR costs under control.
What Is Amazon ECR? (Amazon Elastic Container Registry Explained)
Amazon Elastic Container Registry (ECR) is AWS’s managed service for storing and sharing container images in a secure, scalable registry. It removes the need to run your own registry, maintain storage, patch infrastructure, or build custom authentication systems. You push your images, and AWS handles the rest.
It acts as a secure home for the images your applications rely on. Developers build images locally or in CI, push them to ECR, and your compute services pull the exact digests they need.
This ensures deployments are consistent, predictable, and fully traceable.
Amazon ECR integrates with Amazon ECS, Amazon EKS, Lambda’s container runtime, Batch, and any pipeline that works with Docker registries. It automatically generates immutable image digests, so teams always know the exact version running in production.
See more: The Ultimate Guide To Container Orchestration Tools
ECR also offers image scanning, encryption, IAM-based permissions, and lifecycle rules to control storage. These built-in features reduce engineering overhead and strengthen security without extra tools.
How Amazon ECR Works: Key Features And Core Components
Amazon ECR gives each AWS account a private container registry for Docker and OCI images. You create repositories inside that registry to group images for different services. Every image has a tag and an immutable digest, making versions easy to track, promote, or roll back.
An Amazon ECR repository works like a folder for one workload. When you build a new version, you push a new tag. ECR stores all versions unless you remove them, keeping your deployment history intact across environments.
Amazon ECR stores each image as an OCI manifest with config and layers, and links it to one or more tags.
Amazon ECR also includes a public registry. ECR Public lets you publish images openly and browse AWS images, Kubernetes components, operating system images, and Docker Official Images. Anyone can pull these without an AWS account.
Access control uses IAM policies and repository policies. IAM decides who can call ECR APIs. Repository policies apply fine-grained rules to individual repositories. Docker clients have to authenticate before pushing or pulling from private registries.
Security is built in. Images are encrypted at rest using Amazon S3 server-side encryption or Amazon KMS, and all transfers use HTTPS. ECR supports basic and enhanced scanning via Amazon Inspector to detect OS and language-pack vulnerabilities. You can enable scan-on-push or continuous scanning.
How ECR encrypts container images at rest using AWS KMS.
Lifecycle policies help teams manage storage. You set rules based on age or the number of versions to keep. ECR automatically applies those rules and logs deletion events in CloudTrail, so you can easily audit changes.
Amazon ECR supports cross-region and cross-account replication. You can mirror repositories to other Regions or AWS accounts to reduce latency, support disaster recovery, or enable multi-account setups. A service-linked role handles the replication logic and permissions on your behalf.
Cross region replication in ECR
Pull-through cache rules let you cache images from upstream registries, including ECR Public, Docker Hub, and other OCI-compliant registries. This improves performance, reduces rate-limit issues, and gives you more control over external dependencies.
For networking, ECR integrates with VPC endpoints so your image traffic stays inside AWS. Pulls happen over private networking, reducing latency and avoiding exposure to the public internet.
What Are The Benefits Of Amazon ECR? (Why Amazon ECR Matters For AWS Teams)
Here are some of the benefits engineering and platform teams gain by using Amazon ECR across their AWS environments:
- High availability. ECR stores and serves images across infrastructure spanning multiple Availability Zones. Even during AZ-level disruptions, workloads can still pull images without delays.
- Scalability. Amazon ECR handles multiple image pushes and pulls without manual tuning. Teams do not need to scale storage, run registry nodes, or manage load balancers. Even during peak CI/CD activity, image storage and retrieval remain consistent.
- Faster deployments with local, regional image serving. ECR stores images inside your AWS Region. Services such as ECS and EKS pull them with low latency, improving scale-out speed and reducing cold-start delays.
- Operational simplicity for DevOps. ECR removes the overhead of running your own registry. No servers, patching, certificates, network rules, or storage systems to manage. Teams focus on delivering features instead of operating the image infrastructure.
- Consistent image management across environments. ECR provides a single source of truth for container images. Whether you deploy to dev, staging, or production, teams pull the same trusted image. This reduces drift, simplifies debugging, and improves auditability.
- Reduced risk from public registry dependencies. Pull-through caching reduces reliance on public registries that may have downtime or rate limits. Teams gain more control over upstream images and ensure builds don’t break due to external services.
- Lower costs and storage efficiency. Lifecycle policies help teams avoid unnecessary storage charges by automatically cleaning up stale versions. This ensures registries are organized and predictable, especially when teams ship frequently.
So, how much does Amazon ECR cost?
Amazon ECR Pricing (Storage, Data Transfer, And Scanning Costs Explained)
Amazon ECR uses a pay-as-you-go model.
You mainly pay for:
- ECR storage in public and private repositories
- Data transferred from Amazon ECR to the internet or other Regions
There are no upfront fees or long-term commitments.
Data transferred between ECR and AWS compute services in the same Region (ECS, EKS, Fargate, Lambda, App Runner) is free. That includes pulling images for normal deployments within a single region.
Related read: AWS EventBridge Pricing: A Guide To Charges And Savings
Amazon ECR free tier
ECR includes a free tier for both private and public repositories:
- Private repositories: 500 MB of storage per month for the first 12 months.
- Public repositories: 50 GB of storage per month, always free.
- Public data transfer to the internet:
- 500 GB/month free if you pull anonymously
- 5 TB/month free if you authenticate with an AWS account
Transfers from ECR Public to AWS compute services in any region are unlimited and free.
Beyond the free tier, here are the charges associated with ECR:
Storage
Amazon ECR charges $0.10 per GB-month for image storage in private and public repositories. An Archive tier offers lower rates with a 90-day minimum storage period and retrieval fees.
Data Transfer
Here are the applicable data transfer charges from private repositories:
and in private data transfer from public repositories
Encryption
ECR stores image layers in Amazon S3, so you pay standard S3 storage fees. By default, it uses SSE-S3 encryption at no extra cost. If you enable SSE-KMS encryption (customer-managed key), then AWS KMS request fees and key-usage charges apply. TLS in transit adds no separate encryption fee.
Why Amazon ECR costs can feel complicated
Here is the thing. Amazon ECR pricing doesn’t follow a single model. You pay for image storage, outbound data transfer, and enhanced scanning via Amazon Inspector. ECR also stores images in Amazon S3, so regular S3 storage charges apply, and using KMS encryption adds standard KMS request and key fees.
ECR charges rarely appear under a single line item. Storage and transfer charges surface inside ECS, EKS, Fargate, and network costs. Enhanced scanning is billed under Amazon Inspector. Without tagging or a clear cost view, it becomes difficult to see which repositories, teams, or workloads are driving your ECR spend.
Understand, Monitor, And Optimize ECR Costs With CloudZero
CloudZero connects Amazon ECR actions, pulls, pushes, region hops, replication, scanning, and storage growth to the exact workloads and teams responsible. This turns scattered charges into a clear, shared picture of how container workflows generate cost.
A major insight is that Amazon ECR spend often grows from workflow habits rather than the registry itself. Active CI pipelines push many images a day, and without lifecycle policies, repositories quietly accumulate old and untagged layers. CloudZero surfaces these patterns instantly, helping teams clean up and save on storage costs that would otherwise go unnoticed.
CloudZero also brings context to unexpected Amazon ECR cost spikes. Sudden jumps in data transfer, unusual cross region pulls, or rapid repository growth are flagged immediately. Instead of guessing, teams see the exact service, environment, or pipeline that triggered the change.
This visibility helps engineering make practical decisions. Teams can keep pulls within the same region, tune replication targets, remove unused tags, and place pipelines closer to the registries they rely on. Finance gets accurate attribution, and engineering gets clear, actionable guidance.
With CloudZero, teams at Drift, Rapid7, Malwarebytes, and Skyscanner have saved millions of dollars in AWS costs. To see how, take a quick tour of CloudZero and explore the workflows behind their results. When you’re ready, 
to learn how CloudZero can help your organization turn Amazon ECR and AWS cloud spend into measurable business value.
Amazon ECR FAQs
What is the difference between Amazon ECS and ECR?
Amazon ECS is a container orchestration service for running applications. Amazon ECR is an image registry used to store the container images that ECS runs. ECS schedules and manages containers; ECR stores the images from which those containers are built.
Is Amazon ECR free? (Amazon ECR pricing explained)
No. Amazon ECR charges for image storage and data transfer. You pay for the total amount of image data stored in the registry and any data transferred out of AWS. Within AWS, many pull operations are free.
What is the difference between AWS ECR and EKS?
Amazon EKS is a Kubernetes service for running workloads. Amazon ECR is the image registry that those workloads pull images from. ECR stores images; EKS runs them inside Kubernetes clusters.
Does Amazon ECR charge for data transfer?
Yes. Pulls inside the same region and from ECS/EKS are generally free. Pulls to the internet or other regions incur standard AWS data transfer pricing.
Does Amazon ECR encrypt images?
Yes. ECR encrypts images at rest using Amazon S3-managed encryption by default, or AWS KMS keys if configured. All pushes and pulls use TLS encryption in transit.
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