Top 30 Budget‑Friendly SSO Solutions for Startups and Growing Teams

Developer‑friendly identity platform with a generous free tier (up to 7,000 active users) and easy integration via SDKs and pre‑built connections.

Free developer plan includes unlimited applications and up to 1,000 monthly active users, perfect for prototyping SSO in startups.

Provides basic SSO for Microsoft 365 and thousands of SaaS apps at no cost, with seamless Azure integration.

Built‑in SSO for Google services and over 3,000 third‑party apps; the Basic plan is affordable for small teams.

Free tier includes 50,000 monthly active users and supports SAML, OIDC, and social logins, ideal for AWS‑centric startups.

Directory‑as‑a‑Service with SSO for up to 10 users free; adds device management and LDAP/AD bridges.

Self‑hosted identity solution offering a free tier for up to 1,000 monthly active users and extensive customization.

Open‑source, fully featured SSO server that can be self‑hosted at zero license cost; supports SAML, OIDC, and social providers.

Provides a free plan for up to 5 applications, with easy SAML/OIDC configuration and a low‑cost premium upgrade.

Limited free tier that supports SSO for a handful of apps, suitable for very small teams testing SSO concepts.

Modular, open‑source identity (Kratos) and OAuth2 server (Hydra) that can be combined for a completely free SSO stack.

Community edition offers a self‑hosted, open‑source SSO platform with SAML, OIDC, and LDAP support at no cost.

Enterprise‑grade open‑source IAM that includes SSO, API security, and adaptive authentication for free.

Free for up to 5 users, providing SSO to Google Workspace and hundreds of SaaS apps.

Offers a 30‑day free trial with full SSO capabilities; useful for evaluating a premium solution without upfront cost.

Open‑source authentication platform with a hosted free tier (up to 5,000 MAU) and built‑in SSO flows.

Provides a 30‑day trial of its SSO and access management suite, allowing startups to test enterprise features risk‑free.

Offers a limited‑time free trial with adaptive authentication and SSO for SaaS applications.

Open‑source .NET Core framework for building SSO and OAuth2/OpenID Connect servers; free for non‑commercial use.

Free for up to 5 users; includes password manager plus SSO to popular SaaS apps.

Offers a 14‑day free trial and low‑cost plans that bundle password management with SSO for up to 5 users.

Provides a 30‑day trial of its Privileged Access Service, which includes SSO and MFA for cloud apps.

Free tier for up to 50 users, delivering SSO, MFA, and user lifecycle automation for startups.

While primarily an email alias service, its Business plan (low cost) adds SSO for internal tools.

Free tier includes 50,000 monthly active users with customizable SSO flows for consumer‑facing apps.

Managed Keycloak offering a free starter tier (up to 2,000 MAU) with automatic updates and scaling.

Open‑source session management and SSO solution with a free cloud tier (up to 5,000 MAU) and easy SDKs.

Developer‑first authentication platform offering a free tier (up to 5,000 MAU) that includes passwordless SSO options.

Free up to 1,000 MAU for its API‑first SSO and authorization service, targeting micro‑service architectures.

Even on the free Okta plan, you can use hundreds of pre‑built SSO connectors without extra cost.

Free SDKs and sample apps for implementing SAML SSO in custom applications without a paid license.

Rebranded Azure AD free tier, offering basic SSO to Microsoft and thousands of SaaS apps at zero cost.

A collection of free SSO extensions and connectors that can be added to an Auth0 tenant at no extra charge.