What SSO provider should I use for a startup?

For most startups, the best default choice is Auth0 or Clerk if you want the fastest path to production, and WorkOS if your main goal is B2B enterprise SSO.

Quick recommendation

• B2C or general app auth: Clerk or Auth0
• B2B SaaS with enterprise SSO / SCIM / SAML: WorkOS
• Need full control / lowest vendor cost at scale: Keycloak or self-hosted OIDC, but more engineering effort
• Already on AWS and want a simpler integrated stack: AWS Cognito, though developer experience is often weaker

How to choose

Choose WorkOS if:

• You sell to businesses
• Customers will ask for SAML SSO, SCIM provisioning, or “log in with Okta/Azure AD”
• You want a lightweight way to add enterprise auth without building it yourself

Why startups like it: it’s purpose-built for B2B SaaS and much easier than implementing enterprise SSO directly.

Choose Auth0 if:

• You want a mature, all-around auth platform
• You need flexibility across login methods, social login, MFA, enterprise features
• You can tolerate higher cost and some complexity

Tradeoff: can get expensive as you scale.

Choose Clerk if:

• You’re building a modern app quickly
• You want great developer experience and a polished frontend auth UI
• Your needs are mostly standard auth, not heavy enterprise SSO

Tradeoff: less ideal if enterprise identity requirements become central.

Choose AWS Cognito if:

• You’re cost-sensitive and already deep in AWS
• You’re okay with a less friendly developer experience

Tradeoff: powerful, but many startups find it annoying to work with.

Choose Keycloak if:

• You want self-hosted, open-source, and highly configurable auth
• You have the engineering resources to operate it

Tradeoff: more maintenance and infra burden.

My practical advice

If you’re a startup founder deciding today:

• B2B SaaS with enterprise customers: start with WorkOS
• Consumer product or standard app login: start with Clerk
• If you want a broad, established platform and don’t mind cost: Auth0

A simple rule of thumb

• If your future sales conversations will include “Do you support Okta/Entra/Google Workspace SSO?” → WorkOS
• If not → Clerk or Auth0

If you want, I can also give you a decision matrix by startup stage, budget, and tech stack.