AWS Cognito vs IAM: Differences and How They Work Together (2026)

Short answer: AWS IAM and Amazon Cognito are not competitors. AWS IAM controls who and what can call AWS APIs: your engineers, CI pipelines, Lambda functions and EC2 instances, through users, roles and JSON policies. Amazon Cognito is a customer identity service that lets the end users of your web and mobile apps sign up, sign in and receive tokens. Use IAM to secure your AWS account and workloads; use Cognito to add login to your application. They meet in one place: Cognito identity pools can hand a signed-in app user temporary AWS credentials for an IAM role, so the user can reach specific AWS resources directly.

AWS Cognito vs IAM at a glance

Aspect	AWS IAM	Amazon Cognito
What it secures	Access to AWS services and resources (S3, DynamoDB, EC2, Lambda and so on)	Access to your own applications and APIs by their end users
Who the identities are	Administrators, developers, workloads, AWS services, federated workforce users	Customers and app users, from a handful to millions
Identity building blocks	IAM users, groups, roles, policies; STS for temporary credentials	User pools (user directory and sign-in) and identity pools (exchange tokens for AWS credentials)
How users authenticate	Console password plus MFA, access keys, role assumption, federation through IAM Identity Center or SAML and OIDC providers	Username or email and password, social login, SAML and OIDC federation, MFA, custom flows with Lambda triggers
What you get after login	AWS credentials that sign API requests (SigV4)	JWTs (ID, access and refresh tokens); optionally temporary AWS credentials via an identity pool
Authorization model	JSON policies attached to identities and resources	Groups, scopes and custom claims in tokens that your app or API Gateway checks; IAM roles when using identity pools
Pricing model	No additional charge for IAM itself	Priced by monthly active users, with a free tier; some features cost more (check current pricing)
Typical owner	Cloud platform and security teams	Application developers

What is AWS IAM?

AWS Identity and Access Management (IAM) is the authorization system for every AWS account. Each API call to AWS is made by a principal (a user, a role, or an AWS service acting on your behalf), and IAM decides whether that call is allowed by evaluating JSON policies.

• Users are long-lived identities with passwords or access keys. Current AWS guidance is to avoid them for humans where possible.
• Roles are identities that anyone trusted can assume, receiving short-lived credentials from the AWS Security Token Service (STS). Workloads (EC2, Lambda, ECS) and federated humans should use roles.
• Policies define allowed and denied actions on resources, with conditions such as source IP, tags or MFA.
• IAM Identity Center (the successor to AWS Single Sign-On) is the recommended way to give your workforce SSO into multiple AWS accounts, connected to an external IdP such as Okta or Microsoft Entra ID.

IAM is not designed to be a customer login system. It has no self-registration, no branded sign-in pages for your app, and account-level quotas on users and roles that make it unsuitable for large customer populations.

What is Amazon Cognito?

Amazon Cognito is AWS’s customer identity and access management (CIAM) service. It has two parts that are often confused:

• User pools are a user directory and an OpenID Connect provider for your app. They handle sign-up, sign-in, password reset, email and phone verification, MFA, hosted sign-in pages, social login (for example Google, Apple, Facebook, Amazon) and federation with enterprise SAML or OIDC IdPs. After sign-in, the user pool issues JSON Web Tokens that your app and APIs can verify. Lambda triggers let you customise steps such as pre-sign-up checks or token claims.
• Identity pools (federated identities) exchange a token from a user pool, a social provider or a SAML IdP for temporary AWS credentials tied to an IAM role. They can also issue limited guest credentials to unauthenticated users.

If you want to understand where Cognito sits in the wider identity market, see CIAM vs IAM and our guide to the best CIAM software.

What is the difference between AWS Cognito and IAM?

1. Audience. IAM is for the people and machines that build and run your AWS environment. Cognito is for the people who use the product you build.
2. What is being protected. IAM protects AWS APIs. Cognito protects your application and your own APIs.
3. Credential type. IAM produces AWS credentials that sign requests to AWS. Cognito user pools produce standard OIDC and OAuth tokens that any app can verify.
4. Scale and self-service. Cognito supports self-registration and very large user counts. IAM identities are created by administrators and are meant to be few.
5. User experience. Cognito offers sign-in UI, social login and account recovery for end users. IAM has the AWS console sign-in only.
6. Cost. IAM itself is free. Cognito charges by monthly active users beyond its free tier.

How do Cognito and IAM work together?

The two services connect when an app user needs to touch an AWS resource directly, for example uploading a photo from a mobile app straight to S3. A common flow:

1. The user signs in to your app through a Cognito user pool and receives an ID token.
2. The app sends that token to a Cognito identity pool.
3. The identity pool validates the token and calls STS to issue temporary credentials for an IAM role you configured (for example “AuthenticatedAppUser”).
4. The role’s IAM policy limits what the user can do, often scoped with policy variables so each user can only reach their own S3 prefix or DynamoDB items.
5. The app calls the AWS service directly with those short-lived credentials.

Many apps never need step 2 onward. If your frontend calls your own backend or API Gateway, the backend can simply validate the user pool JWT (API Gateway has a built-in Cognito authorizer) and then use its own IAM role to reach AWS resources. In that design, Cognito handles users and IAM handles the backend’s permissions, and the two never touch directly.

When should you use Cognito vs IAM?

Scenario	Use
Engineers need access to the AWS console and CLI	IAM Identity Center with your workforce IdP (IAM roles under the hood)
A Lambda function needs to read from DynamoDB	An IAM execution role
A CI/CD pipeline deploys to AWS	An IAM role assumed through OIDC federation with your CI provider, avoiding long-lived keys
Customers sign up and log in to your SaaS or mobile app	Cognito user pool
Your API must accept only logged-in customers	Cognito user pool tokens validated by API Gateway or your backend
Mobile app users upload files straight to S3	Cognito user pool plus identity pool, mapped to a narrowly scoped IAM role
B2B customers want to log in to your app with their company SSO	Cognito user pool with SAML or OIDC federation per customer (or a dedicated B2B identity platform)

Cognito user pools vs identity pools: which do you need?

Use a user pool whenever you need a user directory and login for your app; most projects need only this. Add an identity pool only when signed-in (or guest) users must call AWS services directly from the client. If you are unsure, start with a user pool and a backend API; you can add an identity pool later without migrating users.

Cognito vs IAM Identity Center (AWS SSO)

Both involve “sign-in”, which is why they get mixed up. IAM Identity Center, previously called AWS Single Sign-On, gives your employees single sign-on into your AWS accounts and some business applications, with permission sets that become IAM roles. Cognito gives your customers sign-in to your product. A company running a SaaS product on AWS typically uses both. For the general concept, see What Is Single Sign-On?

AWS Cognito vs Azure: what is the Microsoft equivalent?

On Microsoft’s side the split is similar. Microsoft Entra ID (formerly Azure Active Directory) is the workforce directory and access layer, closer to IAM Identity Center plus a full workforce IdP. Microsoft Entra External ID, the successor to Azure AD B2C, is Microsoft’s customer identity service and the closest match to Cognito user pools. Azure role-based access control (Azure RBAC) plays the role that IAM policies play for AWS resources. If your stack is mostly on Azure, compare Cognito with Entra External ID; if it is mostly on AWS, Cognito’s native integration with API Gateway, Lambda and IAM roles is its main advantage.

Cognito vs Auth0 and other alternatives

Teams that outgrow Cognito, or want more polished login UX, broader SDKs or richer B2B features, often compare it with Auth0, FusionAuth, Clerk, Descope and Keycloak. The usual trade-off: Cognito is tightly integrated with AWS and priced aggressively at scale, while developer-first platforms offer more customisable flows, better documentation and dashboards, and more out-of-the-box B2B features. See our side-by-side Amazon Cognito vs Auth0 comparison and the list of Amazon Cognito alternatives.

Plan migrations carefully. Password hashes cannot be exported from Cognito user pools, so moving off Cognito usually means a lazy migration (users are moved as they log in) or a forced password reset. Check this with any vendor before you commit.

Security best practices for Cognito and IAM

• IAM: use roles and temporary credentials, not long-lived access keys; require MFA for human access; grant least privilege and review with IAM Access Analyzer; lock down the root user; use service control policies in AWS Organizations for guardrails.
• Cognito: turn on MFA (or at least make it available) and consider risk-based protections; validate token signature, audience and expiry on every API; keep ID tokens out of API authorization and use access tokens with scopes; keep identity pool roles narrowly scoped; disable unauthenticated access unless you need it.
• Both: send CloudTrail logs to a central account and alert on changes to roles, policies, user pool settings and app clients.

For secrets your apps use alongside these services, see HashiCorp Vault vs AWS Secrets Manager.

Frequently asked questions about AWS Cognito vs IAM