SSO
Single Sign-On
An authentication method where one identity provider grants access across multiple applications.
Definition
Single Sign-On (SSO) allows users to access multiple applications with one set of credentials. Instead of separate logins for each tool, users authenticate once through an identity provider and gain access to all connected applications.
How SSO Works
- User attempts to access an application
- Application redirects to identity provider (IdP)
- User authenticates with IdP (if not already logged in)
- IdP sends authentication token to application
- Application grants access
Common SSO Protocols
| Protocol | Usage |
|---|---|
| SAML 2.0 | Enterprise standard, XML-based |
| OAuth 2.0 | Authorization framework, used with OIDC |
| OpenID Connect (OIDC) | Modern authentication, JSON-based |
SSO Benefits
For Organizations
- Centralized access control
- Easier employee offboarding
- Reduced password fatigue
- Better security visibility
For Users
- Fewer passwords to remember
- Faster access to tools
- Consistent login experience
SSO Pricing Considerations
Many SaaS tools charge extra for SSO - often called the “SSO tax.” Enterprise plans typically include SSO while lower tiers don’t. When evaluating tools, check if SSO is included or requires upgrade.
Identity Providers
Common IdPs that work with most SaaS tools:
- Okta
- Azure Active Directory
- Google Workspace
- OneLogin
- JumpCloud
Frequently Asked Questions
Why do tools charge extra for SSO?
SSO implementation requires development effort and is primarily demanded by enterprises. Many vendors gate SSO behind enterprise tiers as a result. Some view this as problematic since SSO improves security.
What’s the difference between SSO and SCIM?
SSO handles authentication (proving identity). SCIM handles provisioning (creating/updating/removing user accounts). They’re complementary - SSO lets users log in, SCIM manages user lifecycle.
Can I use SSO with smaller tools?
Many smaller SaaS tools support SSO through OAuth (login with Google/GitHub). Enterprise SAML SSO is less common in smaller tools but increasingly available.