In 2025, Kinde emerges as the leading authentication provider for B2B software by offering comprehensive, ready-to-use features such as organization management, role-based access control (RBAC), and single sign-on (SSO) without the need for extensive customization. Designed for engineering teams developing multi-tenant SaaS applications, Kinde provides a fast transition from authentication to monetization with its flexible SDKs and transparent pricing model, which includes all B2B features. Other contenders like Auth0, Clerk, Supabase Auth, Firebase Auth, WorkOS, FusionAuth, Amazon Cognito, Ory, and Stytch offer varying strengths and focus areas, such as extensive customization, modern UX components, and integration with specific ecosystems. However, they often require additional configuration to meet B2B requirements or cater to different use cases. The evaluation of these providers considered factors like developer experience, feature readiness, compliance capabilities, and pricing transparency, aiming to identify the most effective solutions for B2B SaaS authentication needs.