Best SSO Providers in 2026: How to Choose the Right One for Your App

Every SSO provider claims the same three things: SAML and OIDC support, adaptive MFA, and enterprise-grade security. On paper, the best SSO providers all look interchangeable. The differences only surface once you're onboarding your fiftieth enterprise customer and their IT team wants to connect an identity provider your current setup was never tested against.

That’s the actual evaluation problem in 2026: not whether a platform supports SAML (they all do), but whether it was built for multi-tenant customer identity from the ground up. Descope, Auth0, Amazon Cognito, Microsoft Entra External ID, WorkOS, Firebase Authentication, OneLogin, Stytch, and Keycloak handle federation differently once you get past the checkbox comparison, especially on tenant configuration, self-service onboarding, and how much of your engineering team gets pulled into every new customer's SSO setup.

This breakdown covers where each of these nine SSO providers earns its place, where each falls short, and which SSO service provider fits your tenant model, whether you're closing your first enterprise deal or your five-hundredth.

At a glance

• The best SSO providers for customer identity in 2026 combine SAML/OIDC/SCIM support with multi-tenant configuration and self-service onboarding for enterprise customers.

• Descope leads for B2B SaaS teams that need tenant-aware SSO with adaptive MFA and visual workflow tooling, supported by a Free Forever tier.

• Auth0, Amazon Cognito, Microsoft Entra External ID, and WorkOS each serve specific ecosystem-aligned use cases: enterprise federation, AWS-native, Microsoft, and developer-first B2B respectively.

• Open-source options like Keycloak offer full infrastructure control but require dedicated DevOps for deployment, patching, and scaling.

• Choosing the right provider depends on your tenant complexity, cloud ecosystem, pricing model preference, and whether you need support for non-human identities like AI agents and service accounts.

Quick facts

What is customer SSO?

Customer SSO enables users from outside your organization (clients, business partners, tenants) to authenticate once and access multiple connected applications. It establishes trust between your apps and an identity provider (IdP) using standards like SAML, OIDC, or OAuth 2.0.

Unlike workforce SSO, which manages employee access within a single enterprise, customer SSO handles external audiences with disparate IdPs, branding needs, and security expectations. Workforce SSO assumes greater visibility and control over the user base; customer SSO needs the flexibility to accommodate variety.

Its core components:

• Federation protocols: SAML and OIDC allow trust relationships between apps and identity providers, enabling identity federation.

• Adaptive MFA: Step-up verification layers triggered by risk signals like device, location, or IP anomalies.

• Tenant-aware configuration: Per-customer or per-partner SSO without code duplication.

• SCIM provisioning: Automated user and group sync between systems.

• Self-service onboarding: Customer admins configure and test their own SSO connection, reducing developer overhead.

How do the best SSO solutions work?

SSO lets users authenticate once and access multiple connected applications through a trusted identity provider. Most modern SSO systems use SAML or OIDC to exchange trust between the IdP and each service provider.

Here are the steps for Service Provider (SP)-initiated SSO:

1. The user requests access to an app.

2. The app redirects to the IdP for authentication.

3. The IdP verifies the user, applies MFA or risk checks, and issues a token.

4. The app validates the token and grants access.

SP-initiated SSO is preferred for customer-facing applications because the service provider controls the flow context: it knows which tenant is requesting access and can route to the correct IdP accordingly. This is what makes tenant-aware federation practical. An enterprise customer connecting Azure AD to your SaaS platform doesn’t require hardcoded configuration on either side.

Initiating SSO through the SP rather than the IdP is more flexible. It allows for tenant-aware federation, such as an enterprise customer seamlessly connecting Azure AD to a SaaS platform.

Also read: IdP vs SP-initiated SSO

What to look for when choosing an SSO provider

Choosing the right customer SSO platform depends on your users, architecture, and security requirements. Most providers handle basic authentication and federation; what separates them is how well they handle the complexity of customer-facing environments.

Here are the criteria that matter most:

• Standards support: Compatibility with SAML, OIDC, and SCIM to connect with any IdP.

• Tenant management: Multi-tenant or per-customer SSO configuration to simplify onboarding at scale.

• Self-service setup: Customer admins can configure and test SSO independently, without filing tickets.

• Simplified on/offboarding: Customers provision and deprovision users through their existing IdP.

• Adaptive security: MFA, device checks, and risk-based access control that respond to context.

• Developer experience: SDKs, APIs, and no-code workflows that reduce integration time.

• Scalability and cost: Pricing and performance that grow with your customer base, not against it.

• Pricing transparency: Whether pricing is published, usage-based, or locked behind a sales call. Opaque pricing is a common frustration when evaluating SSO providers, and it’s an avoidable one; teams want to model costs before they commit, not after., not after.

• AI and agent identity support: Whether the platform can manage non-human identities: service accounts, AI agents, and MCP tool-execution workflows. As agentic architectures become production infrastructure, identity management for machines is no longer optional.

Also read: 7 Benefits of Single Sign-On (SSO)

The best SSO providers for customer SSO

The comparison below covers nine providers, each with different strengths depending on your tenant model, cloud ecosystem, and engineering capacity. The table is followed by deeper analysis of each platform.

1. Descope

Best for: B2B and B2B2X SaaS platforms that need tenant-aware SSO with self-service onboarding, adaptive MFA, and visual workflow tooling.

Descope is a customer identity and access management (CIAM) platform built specifically for customer SSO and tenant-aware federation. Designed for both B2C and B2B applications, it provides tenant-aware SSO, organization management, and self-service onboarding tools that make it straightforward for every customer or partner to connect their own IdP.

With built-in support for multi-tenancy, partner integrations, and identity for AI agents and MCP ecosystems, Descope helps teams unify authentication across human users, services, and intelligent agents. Its native SAML, OIDC, and SCIM support removes the friction of enterprise integrations, allowing each tenant to manage their own SSO configuration through a guided, branded experience.

Descope was founded in 2022 by a team of serial cybersecurity entrepreneurs who previously founded Demisto, a leader in the Security Orchestration, Automation and Response (SOAR) space that Palo Alto Networks acquired. The company launched from stealth in February 2023 with $53M in seed funding and has since grown to serve thousands of organizations, save time for tens of thousands of developers, and manage hundreds of millions of total identities. That shows up in the architecture: tenant SSO configuration, MFA policies, and federation logic all live in the platform, not in your codebase.

Key capabilities

• SSO Setup Suite: Customer and partner SSO with SAML, OIDC, and SCIM. Includes a self-service SSO Setup Suite that lets customer admins configure, test, and manage their own connections.

• Multi-tenancy: Different auth, branding, and access control requirements across B2B customers, partners, and other stakeholders. Multiple IdPs per SSO connection for larger enterprise customers.

• Granular authorization: Users, roles, and permissions organized across tenants with integrated RBAC and fine-grained authorization (FGA).

• Visual workflow editor: Build and modify authentication, onboarding, and MFA flows without writing code.

• Identity federation: Unified auth flows across multiple apps and IdPs with real-time business logic execution.

• Adaptive MFA and security controls: Context-aware MFA, session management, and bot detection that respond dynamically to risk.

• Extensive SDKs and APIs: 15+ web, mobile, and backend SDKs plus a full REST API for custom SSO and identity integrations.

• Connector ecosystem: Third-party integrations for risk, fraud, analytics, and directory sync.

• Embeddable UI widgets: Branded, self-service identity management administration within your app.

• Identity orchestration: Authentication, authorization, and risk evaluation coordinated across multiple systems in one visual flow.

Strengths

• Tenant-aware SSO at scale: Descope’s architecture is built around multi-tenant SSO. Each customer or partner can connect their own IdP through self-service onboarding, reducing manual setup while maintaining centralized control and visibility.

• Self-service customer onboarding: The SSO Setup Suite lets customer administrators configure, test, and manage SSO and SCIM integrations on their own, without filing tickets or waiting on your engineering team.

• Smooth migration experience: SSO Migration lets organizations transition existing SAML or OIDC configurations to Descope without downtime or forcing tenants to reconfigure their IdPs.

• Visual workflows: No-code editor simplifies auth design, reducing time to production.

• Dynamic identity federation: Bridge many-to-many identity relationships without hardcoding federation flows.

• Passwordless authentication: Built-in passkeys, magic links, OTPs, and social login.

• Omnichannel authentication: Unified flows for web, mobile, and partner apps.

• Adaptive MFA: MFA enforced only when risk signals are detected, with multiple MFA options.

• Developer flexibility: SDKs and APIs for modern frameworks, with hosted or custom UI options.

• Transparent pricing and support: Every Descope tier includes bundled SSO connections (3 on Free, 5 on Pro, 10 on Growth), with per-unit overages only past your allocation, rather than billing per connection from the very first one. See the pricing page for current details.

Limitations

• As a newer platform compared to legacy providers like Okta or Auth0, Descope has a smaller third-party marketplace, though its core integration catalog and connector ecosystem are growing rapidly.

Also read: The Developer’s Guide to Implementing Single Sign-On

2. Auth0

Best for: Organizations that need a mature, enterprise-ready customer SSO solution with deep federation support and extensive customization.

Auth0 is a well-established platform for customer SSO and external identity management. It connects enterprise customers and partners through standards-based federation, supporting SAML, OIDC, and social IdPs. With hosted authentication, adaptive MFA, and role-based access control, Auth0 delivers strong security and customization for customer-facing applications.

Key capabilities

• Hosted login pages with branding, customization, and localization

• SAML, OIDC, and social provider federation for customer SSO

• Role-based access control (RBAC) and adaptive MFA

• Extensibility through Actions, Hooks, and APIs

• Admin dashboard for managing users, connections, and activity logs

Strengths

• Enterprise-grade federation: Deep SAML and OIDC support for customer and partner IdPs, with mature tooling for complex connection configurations.

• Proven reliability: Used by thousands of SaaS and enterprise applications, with strong uptime and well-staffed support.

• Developer ecosystem: Wide SDK coverage, thorough documentation, and a marketplace of pre-built integrations.

Limitations

• Pricing escalates significantly at scale, particularly when adding enterprise SSO connections as paid add-ons. Teams running high volumes of tenant connections often find costs harder to predict than initial tiers suggest.

• Multi-tenancy is layered on rather than native. Auth0’s Organizations feature adds B2B multi-tenancy on top of an architecture that wasn’t originally built tenant-first, which can surface as complexity in per-tenant configuration and isolation as you scale. (See Descope vs. Auth0 for B2B auth and SSO).

3. Amazon Cognito

Best for: Teams already on AWS that need customer SSO tightly integrated with their existing cloud stack.

Amazon Cognito is AWS’s managed authentication and authorization service for customer and partner-facing applications. It supports SAML, OIDC, and social identity providers while leveraging AWS’s global infrastructure for scalability. Cognito offers user pools for direct authentication and identity pools for temporary AWS credential access.

Key capabilities

• SAML, OIDC, and social provider federation for customer SSO

• Managed user pools for authentication and identity pools for AWS access

• Integration with AWS services like API Gateway, AppSync, and IAM

• Custom logic and triggers through AWS Lambda functions

• MFA support and fine-grained access control policies

Strengths

• AWS-native integration: Tight interoperability with the broader AWS ecosystem.

• Scalability: Built on AWS infrastructure with automatic scaling and regional availability.

• Federation flexibility: Supports major IdPs including Azure AD, Okta, and Google.

Limitations

• UI customization is limited compared to dedicated CIAM platforms. Teams that need branded, white-labeled login experiences often hit walls with Cognito’s hosted UI options.

• Multi-tenant SSO requires workarounds: Cognito doesn’t natively support per-tenant IdP configuration the way purpose-built CIAM platforms do, which means more custom code as tenant counts grow.

Descope enhances AWS-native auth with an AWS SaaS Builder Toolkit plugin that automates multi-tenant authentication, user management, and secure M2M flows. It can also augment Cognito as an OIDC provider.

4. Microsoft Entra External ID

Best for: Organizations deep in the Microsoft ecosystem that need customer or partner SSO with enterprise-grade governance.

Microsoft Entra External ID extends beyond workforce identity to support external customer and partner SSO. It federates access for clients, vendors, and B2B users using SAML, OIDC, or social identity providers, with built-in governance, conditional access, and auditing.

Key capabilities

• Customer and partner SSO via SAML, OIDC, and social providers

• Conditional access and adaptive MFA for risk-based authentication

• Lifecycle management with automated provisioning and access reviews

• Custom-branded sign-up and sign-in experiences

• Integration with Microsoft 365, Azure, and Power Platform

Strengths

• Enterprise governance: Identity management, compliance, and audit controls for external users in one place.

• Ecosystem integration: Direct connection with Microsoft 365, Azure, and Power Platform without third-party middleware.

• Scalable federation: Handles large B2B and B2C identity volumes with granular policy control.

Limitations

• Tightly coupled to the Microsoft ecosystem. Teams running multi-cloud or non-Microsoft infrastructure often find External ID less flexible than vendor-agnostic alternatives.

• External ID capabilities are still maturing relative to the workforce-focused Entra features. Some B2C-specific functionality lags behind what dedicated CIAM platforms offer.

5. WorkOS

Best for: Developer-led B2B SaaS teams that need to pass enterprise security reviews quickly with SSO, SCIM, and audit logs.

WorkOS is a developer-focused platform built to make B2B SaaS applications enterprise-ready. Rather than providing end-to-end CIAM, WorkOS concentrates on the specific features enterprise buyers demand during procurement (SSO, directory sync, audit logs, and fine-grained authorization) and wraps them in clean APIs with strong documentation.

WorkOS is a developer-focused platform built to make B2B SaaS applications enterprise-ready. Rather than providing end-to-end CIAM, WorkOS concentrates on the specific features enterprise buyers demand during procurement (SSO, directory sync, audit logs, and access control) and wraps them in clean APIs with strong documentation.

Key capabilities

• SAML and OIDC SSO with an Admin Portal for customer IT teams to self-manage connections

• SCIM-based directory sync to keep users and groups current

• Audit logs for security and compliance visibility

• Fine-grained authorization, added to the platform through an acquisition, running as a separate Zanzibar-style authorization service alongside AuthKit rather than as part of the original authentication architecture

• AuthKit: a free authentication layer supporting email/password, social login, and MFA for up to 1 million MAUs

Strengths

• Fast time-to-enterprise-readiness: WorkOS’s focused scope means teams can ship SSO and SCIM in days rather than weeks, which matters when a deal is waiting on a security review.

• Developer experience: Clean APIs, thorough documentation, and SDKs that stay out of the way.

• Published per-connection pricing: $125/connection/month with automatic volume discounts, dropping to $65 at 51-100 connections. AuthKit is free up to 1M MAUs.

Limitations

• Narrower scope than full CIAM platforms. WorkOS focuses on the enterprise-readiness layer (SSO, SCIM, audit logs, access control) rather than end-to-end identity orchestration, passwordless flows, or visual workflow tooling. Teams that need broader identity management will likely need to pair WorkOS with additional tools.

• Primarily B2B-oriented with limited B2C features. If your product serves both enterprise customers and individual consumers, you may outgrow WorkOS’s scope.

• Per-connection pricing scales linearly with enterprise customer count, so cost climbs in step with the number of tenants you connect rather than flattening out. 

• No FedRAMP High authorization or multi-region data residency, which can be a blocker for public-sector buyers and enterprises with data-localization requirements. (See the enterprise-readiness comparison on Descope vs. WorkOS.)

Comparing SSO providers is the first step. Seeing how tenant-aware SSO actually works is the next. Descope’s Free Forever tier includes visual workflows, adaptive MFA, and multi-tenant SSO (3 SSO connections and up to 10 tenants), with no credit card required. Self-service SSO configuration is available on Pro and SCIM on Growth. Sign up free.

6. Firebase Authentication

Best for: Startups and mobile-first teams that need lightweight auth fast within the Google Cloud ecosystem.

Firebase Authentication, part of Google’s Firebase platform, provides lightweight authentication for web and mobile apps with basic support for SSO through SAML and OIDC. Designed for speed and simplicity, Firebase Auth helps developers enable sign-in with minimal setup.

Key capabilities

• SAML and OIDC federation for basic customer SSO

• SDKs for web, iOS, Android, and cross-platform frameworks

• Email/password, phone, and social provider authentication

• Prebuilt and customizable UI libraries for login and signup

• Integration with other Firebase services like Firestore and Cloud Functions

Strengths

• Ecosystem fit: Tight integration with Google Cloud and Firebase developer tools.

• Fast implementation: Quick setup and easy integration across multiple platforms.

• Developer-friendly: Strong SDK support and minimal configuration for rapid prototyping.

Limitations

• Limited enterprise federation and multi-tenant management. Firebase Auth wasn’t built for the complexity of B2B customer identity with per-tenant IdP configuration.

• No native SCIM support, which means directory sync with enterprise customers requires custom implementation.

• Not suited for complex B2B customer identity scenarios where tenant isolation, per-customer branding, and granular access control are requirements.

7. OneLogin Customer Identity

Best for: Mid-market and enterprise organizations that need reliable, centrally managed SSO without extensive customization.

OneLogin provides a unified platform for customer and partner SSO, MFA, and access management. It supports SAML, OIDC, and OAuth 2.0, with an admin console, policy-based access controls, and a broad library of prebuilt connectors.

Key capabilities

• SAML, OIDC, and OAuth 2.0 support for customer and partner SSO

• Centralized identity management and access policy configuration

• Risk-based MFA with multiple verification options

• Directory synchronization and automated user provisioning

• Admin dashboard for application and user lifecycle management

Strengths

• Strong security posture: Risk-based MFA and contextual access policies for external users.

• Straightforward administration: Easy-to-use console for managing users, groups, and access policies.

• Extensive connector catalog: Integrations with thousands of SaaS applications and identity providers.

Limitations

• Less developer flexibility compared to API-first platforms. Teams that want to build custom auth flows or embed identity deeply into their product UX may find OneLogin’s approach more rigid.

• Pricing is not publicly transparent. It requires sales engagement, which makes cost modeling harder during early evaluation.

8. Stytch

Best for: Engineering-heavy teams that want full API-level control over their auth experience without a visual abstraction layer.

Stytch is an API-first authentication platform that gives developer teams granular control over every aspect of the auth experience. It supports SAML and OIDC SSO, passwordless authentication, organization management for B2B, session management, and fraud detection. In 2025, Stytch introduced Connected Apps, which lets any application act as a fully compliant OAuth 2.0/OIDC identity provider, a feature that extends to AI agent authentication and MCP-based tool-execution workflows.

Stytch was acquired by Twilio in late 2025 and continues to operate as a product within Twilio’s platform.

Key capabilities

• SAML and OIDC SSO for customer and partner federation

• Passwordless authentication including magic links, OTPs, and WebAuthn

• Organization management for B2B multi-tenant use cases

• Session management with token, JWT, or hybrid approaches

• Connected Apps for OAuth 2.0/OIDC provider configuration and AI agent identity

• Fraud and bot detection built into the auth layer

Strengths

• Developer experience: Clean API design with granular control over auth flows, sessions, and token lifecycle.

• API-first architecture: Everything is programmable, which suits teams that want to own the UX end-to-end.

• Connected Apps: Enables OAuth-based integrations and AI agent authentication, with org-level policy controls and human-in-the-loop approvals.

Limitations

• Building a complete auth experience with Stytch often means assembling capabilities from separate APIs, which increases custom engineering as your requirements grow. (See Stytch alternatives and Descope vs. Stytch.)

• Visual workflow tooling is minimal. Most customization requires code, which increases implementation time for teams without dedicated auth engineering resources.

• Per-MAU pricing can scale unfavorably for B2B SaaS with large, infrequently active user bases. Enterprise SSO connections are priced per connection without the volume-discount ladder some competitors offer.

• Twilio’s acquisition has introduced questions about long-term product roadmap independence, particularly around whether B2B features will keep pace with Twilio’s broader communications platform priorities.

9. Keycloak

Best for: Organizations with dedicated DevOps or engineering capacity that want to self-host customer SSO and maintain full control over identity infrastructure.

Keycloak is an open-source identity and access management platform that supports customer SSO through SAML, OIDC, and OAuth 2.0. It gives organizations full control over their authentication environment, including realm-based configuration, custom themes, and integration with external directories like LDAP or Active Directory.

Key capabilities

• SAML, OIDC, and OAuth 2.0 for customer and partner SSO

• Integration with LDAP and Active Directory

• Realm-based configuration for multi-tenant management

• Customizable login themes and localization

• Role-based access control (RBAC) and fine-grained permissions

Strengths

• Standards-based federation: Broad protocol support for connecting enterprise IdPs and external customers.

• Full control: Self-hosted and open source, giving teams complete flexibility over deployment and customization.

• Community-driven: Active open-source ecosystem with broad documentation and extensions.

Limitations

• Requires dedicated DevOps for deployment, upgrades, patching, and scaling. Keycloak doesn’t run itself; teams need to budget for ongoing operational overhead.

• No managed SaaS option from Red Hat. If you want hosted Keycloak, you’re looking at third-party providers or running it yourself on Kubernetes.

• Enterprise tooling like compliance dashboards, advanced audit logging, and centralized analytics requires community extensions or custom development rather than being available out of the box.

How to choose the best SSO provider for your organization

The right choice depends on what you’re actually optimizing for. Use this decision matrix to narrow the field:

For B2B SaaS teams managing external customers and partners across multiple tenants, Descope’s combination of tenant-aware SSO, self-service setup, visual workflows, and transparent pricing makes it worth evaluating, particularly if your identity needs extend to AI agents and non-human identities alongside traditional user authentication.

Start building secure customer SSO today

Customer SSO becomes a competitive advantage when it matches your architecture, your customers’ identity providers, and your growth trajectory. Descope’s tenant-aware SSO, self-service setup, and visual workflow tooling are built for teams that want to ship enterprise-ready auth without building it from scratch.

Sign up for a Free Forever account and start building secure, scalable auth flows today. Have questions about customer SSO and CIAM? Book time with the Descope identity team.

Frequently asked questions about SSO providers