Signing into a digital resource, like a website or app, is a regular part of modern life. But behind that seemingly simple action is a detailed process that’s taken many years and — input from many people and companies — to develop. Identity management, including sign-in, is underpinned by a series of protocols. These protocols handle the online transactions between people and systems. One of the most common identity protocols is OpenID Connect (OIDC), which can be used to implement single sign-on (SSO).

Here, AccessOwl looks at the use of OIDC with SSO and the implementation of best practices.

What is OIDC (OpenID Connect)?

OpenID Connect, or OIDC, is an identity authentication protocol developed by the OpenID Foundation. It handles the verification of a user's identity when they attempt to access a resource, like an app. OIDC also facilitates the sharing of user claims, like name, email address, etc. It’s a standard built upon OAuth 2.0 and uses the authorization mechanisms that are part of that protocol. 

Many types of apps and services use OIDC, including single-page web apps (SPA) and native and mobile apps. OIDC also handles single sign-on (SSO) across OIDC federated applications. As of 2025, more than 80 percent of modern SSO implementations now use OIDC over legacy protocols like SAML.

What is SSO (single sign-on)?

Single sign-on (SSO) allows users to log in once and access multiple systems without needing to authenticate again in each one. It reduces password fatigue, minimizes login errors, and improves security by centralizing identity enforcement.

For employees who use multiple SaaS apps each day, SSO offers a more seamless experience. Instead of managing dozens of passwords, users authenticate once through a trusted provider and gain access to all connected apps. When paired with OIDC, SSO becomes even more efficient and developer-friendly—especially for companies that prefer modern identity protocols and RESTful APIs over legacy XML-based systems.

Benefits of using OIDC for SSO

OIDC, when used to implement SSO, offers a company several essential benefits:

Simplifies authentication

OIDC-based SSO lets users authenticate once through a trusted identity provider (IdP), then access multiple connected services without re-entering credentials. This makes sign-in fast and consistent across tools, especially when using providers like Google, Microsoft, or Auth0.

Centralizes access control

SSO is a way to centralize access control management. Centralized access control provides better visibility and the ability to monitor access events, reducing provisioning errors and mitigating unauthorized access.

Improves security

Instead of passing passwords, OIDC exchanges digitally signed tokens—such as ID and access tokens—between systems. These tokens are tamper-proof and short-lived, limiting the risk of credential theft or reuse. OIDC also supports optional token encryption, improving data protection in regulated environments. Because passwords are never reused across apps, credential exposure risks are significantly lower.

Provides consent to share data

One innovative feature of OIDC that sets it apart from identity protocols like SAML is that consent to share data is built into the protocol. OIDC is often used in consumer-facing services, where data sharing requires consent for compliance with regulations like GDPR.

SSO implementation best practices

Any app or web service designer can integrate with an OpenID provider (OP), such as a social network like GoogleID. The app or service must present a UI, such as a button, allowing users to connect to their OP login. The following best practices when implementing SSO via OIDC should be considered:

Multi-factor authentication (MFA)

Single sign-on should be used with robust authentication measures, such as MFA. Examples of MFA measures include mobile app authenticator codes or biometrics.

Step-up or risk-based authentication

Trigger additional authentication based on behavioral or contextual risk. For example, users logging in from new devices, unusual locations, or during high-risk transactions can be prompted for reauthentication. OIDC supports these flows through authorization policies and session context tokens.

Real-time monitoring

SSO offers central visibility into who’s logging in, when, and where. This makes it easier to detect unauthorized access, brute force attempts, or inactive accounts. Solutions like AccessOwl can enhance OIDC SSO by layering in shadow IT discovery, role-based reporting, and automated access reviews across all federated tools. As shadow IT grows in SaaS-heavy companies, combining OIDC with continuous monitoring is now a best practice for identity governance.

Single logout

OIDC supports single logout (SLO), but implementation can be tricky. Users may be signed in across multiple apps at once and SLO needs to either log them out of all apps or let them choose which to leave. Most orgs today offer user-driven SLO options that let employees control which sessions to end without disrupting workflows.

Example of OIDC SSO

Let’s say your company integrates Google Sign-In into your internal dashboard. When a user clicks “Sign in with Google,” they’re redirected to a secure Google login screen. Once authenticated, they’re returned to your app already signed in. From that point forward, the user can also access other Google-federated apps like Drive, Gmail, or third-party SaaS tools without reauthenticating. The OIDC token exchange handles identity across all connected services. This is OIDC SSO in action: fast, secure, and invisible to the user once set up.

OIDC vs. SAML for SSO

Both OIDC and SAML support SSO. However, they differ in how they’re implemented and the types of use cases supported.

OIDC was built to support more consumer-facing use cases and is designed for use with social federated logins like AppleID, Google Sign-In, and Facebook. OIDC is built upon OAuth 2 and handles modern requirements for consented data sharing. OIDC is also considered a “lightweight” protocol, as its architecture is based upon JSON web tokens (JWTs), which have reduced processing needs. OIDC is based on the modern architectural standards of JSON and RESTful APIs.

SAML is an older protocol developed before the advent of federated social logins. It’s often used in enterprises that must support legacy applications. SAML is based on a larger, more complex XML document schema. It was not designed for use with single-page applications (SPAs) and mobile apps.

Both SAML and OIDC can be implemented securely, but SAML is typically considered more secure than OIDC. Security, however, comes down to the implementation of the protocol rather than the protocol itself.

OIDC SSO and user provisioning and deprovisioning

User provisioning and deprovisioning is an important aspect of identity management. As employees join or leave a company, their access rights, including SSO rights, must be added or removed. Automation of identity provisioning and deprovisioning ensures that an employee's SSO access is removed when they leave, canceling access across all federated apps. This improves the company's overall security posture and compliance. Identity governance platforms like AccessOwl provide automation of identity provisioning and deprovisioning.

SSO and shadow IT

Employees may be tempted to sign up for apps using free or cheap trial subscriptions. Unsanctioned apps are a compliance, legal, and security nightmare. This problematic shadow IT creates security gaps, as the SaaS apps are unmanaged. Company data flows are then incorporated into these unvetted apps.

Shadow IT is a gray area in IT and requires mechanisms, like app discovery, to bring them under company control. Modern governance solutions, like AccessOwl, make shadow IT apps visible, creating a single source of truth. AccessOwl's shadow IT register collates all apps, including shadow IT apps. Apps can then be federated with an OIDC identity provider (OP) to facilitate SSO. Employees then benefit from a consolidated app login across all apps. Companies benefit from having surety that their access controls reflect the employee’s role and its own security policies.

When combined with OIDC SSO, AccessOwl creates a single source of truth across your SaaS environment. You get better security, less friction, and complete confidence in your access posture.

Conclusion

OIDC-based SSO has become the backbone of modern identity management—especially for SaaS-first, remote-enabled, and high-compliance teams. With the right implementation and the right governance tools, you can improve security, reduce friction, and build an identity foundation that scales.