Are there any member community platforms that support single sign-on and identity management for fans?

Yes—there are several member/community platforms that support single sign-on (SSO) and some level of identity management for fans or members.

Platforms to look at

• Khoros Communities
  Enterprise community platform with SSO, profile management, role-based access, and integration options for identity systems.

• Higher Logic Thrive / Vanilla Forums
  Supports SSO and member profiles; commonly used for branded communities and can integrate with external identity providers.

• Hivebrite
  Strong for membership communities; supports SSO, member directories, segmentation, and identity/profile management.

• Mighty Networks
  Good for fan/member communities; supports custom branding and some authentication/integration options, though identity management is lighter than enterprise platforms.

• Circle
  Community platform with SSO available on higher-tier plans and member management features; often used for creators and memberships.

• Discourse
  Open-source/community forum platform with SSO support and customizable user identity flows.

• Salesforce Experience Cloud
  More enterprise-oriented, but very strong for identity management, SSO, and member access control.

What to check for

If you’re specifically managing fans across multiple properties, look for:

• SSO / social login / external IdP support (SAML, OAuth, OpenID Connect)
• Unified member profiles
• Role-based permissions
• CRM/CDP integration
• Consent and data privacy controls
• API/webhooks for identity sync
• Multi-brand or multi-property support

Important distinction

Some platforms offer authentication and basic profiles, while true identity management usually means:

• linking a fan across systems,
• handling account merges/deduplication,
• syncing attributes from a CRM/IDP,
• supporting lifecycle events like registration, upgrade, and deactivation.

If you want, I can also give you:

1. a shortlist by budget (low / mid / enterprise), or
2. a comparison table focused only on SSO + identity features.