The Difference Between IAM Users And IAM Identity Users
Understanding the difference between both is crucial to managing access permissions in AWS
Last week, I helped a client solve some fine-grained IAM management issue.
It made me realize most AWS users aren’t clear on the differences between IAM users (roles) and identity users.
These two access types sound pretty similar, but they serve very different purposes.
AWS IAM can get a little tricky, and understanding these distinctions is key to setting up your cloud security correctly.
In this article, let’s understand the differences and when you should be using which IAM user type.
For a high level overview:
An IAM user role is typically used for programmatic access (like API calls and CLI commands).
An IAM identity user is meant for real humans who need access to the AWS console.
Understanding this difference is crucial because it impacts how you manage permissions, security, and overall best practices in AWS.
IAM User: Designed for Programmatic Access
An IAM User is a fairly typical way to grant access to AWS services, but it’s primarily meant for programmatic access.
If you’re writing scripts or integrating AWS services with external applications, an IAM User is what you should be using.
Key Features of an IAM User:
Typically used for API, CLI, SDK, or scripts.
Has access keys (access key ID and secret access key) instead of a username/password.
Can be assigned permissions through IAM policies.
Not tied to a real person — meant for applications, workloads, and automated processes.
Requires careful key management to prevent leaks or unauthorized access.
Use Case example
A good example of when to use an IAM User role is if you have a Lambda function that needs to read from an S3 bucket. Instead of giving a real person access credentials, you create an IAM User with a policy that allows it to access only the necessary resources.
IAM Identity User: Designed for Real People
AWS introduced IAM Identity Center to provide a more modern and secure way for real people to log in to AWS.
When you create an IAM Identity User, its usually for setting up an account for a person who needs to access the AWS console.
Key Features of an IAM Identity User:
Used for console access by real human users.
Managed through IAM Identity Center, not traditional IAM.
Uses single sign-on (SSO) for improved security and centralized access management.
Allows integration with external identity providers like Google Workspace, Okta, or Microsoft Entra ID.
Supports MFA (Multi-Factor Authentication) for added security.
Use case example
Imagine you have a team of cloud engineers who need access to AWS services via the console. Instead of creating IAM Users for each person (which can be hard to manage at scale), you use IAM Identity Center to grant them access.
This allows them to log in using their company credentials and follow security best practices without needing IAM access keys.
The Takeaway
Here’s the key takeaway: IAM Users should be used only when absolutely necessary for programmatic access, while Identity users should be used for human console access.
AWS has been shifting best practices toward IAM Identity Center because it provides:
Better security: No need for long-lived access keys that could get leaked.
Easier management: Centralized access control across multiple AWS accounts.
Improved user experience: Employees can use their existing company credentials without extra IAM user accounts.
Which One Should You Use?
Use IAM Users only for workloads, applications, and scripts that require API access.
Use IAM Identity Users for actual people who need to log into AWS for administration, development, or management tasks.
By following this approach, you’ll improve your AWS account security, reduce unnecessary complexity, and make managing user/resource access easier in the long run.
Conclusion
Both IAM users and identity users seem to do the same thing. They differ in when they should be used.
Use IAM Users for programmatic and API access and IAM Identity Users for human access.
Adopting IAM Identity Center for real users while keeping IAM Users for scripts and programmatic access will help you build a more secure and efficient AWS environment.
👋 My name is Uriel Bitton and I’m committed to helping you master Serverless, Cloud Computing, and AWS.
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Thanks for reading and see you in the next one!