Auth0 Alternatives for Europe: Self-Hosted Identity That Meets GDPR
Compare the best Auth0 alternatives for European businesses: Zitadel vs Auth0, Keycloak vs Auth0, and more self-hosted identity providers that keep your data in the EU.
Auth0 was the default choice for identity management for years. Then Okta acquired it, pricing changed, and suddenly a lot of European businesses started asking uncomfortable questions about where their users' data actually lives.
Here's the problem: Auth0 is a US company. Okta is a US company. Under the CLOUD Act, US authorities can compel American corporations to hand over data regardless of where it's stored. You can host your Auth0 tenant in the EU all you want. The legal exposure remains. For businesses handling sensitive user data under GDPR, this is not a theoretical risk. It's a compliance gap.
The Auth0 Pricing Problem
Even if you're comfortable with the data residency situation, Auth0's pricing deserves scrutiny. The free tier caps at 7,500 monthly active users. That sounds generous until your app grows. After that, you're looking at $35/month for 500 machine-to-machine tokens on the Essentials plan, and costs escalate fast from there. Enterprise pricing is deliberately opaque.
Self-hosted alternatives eliminate per-user pricing entirely. You pay for the server, and that's it. For a growing European SaaS company, the difference over 12 months can be thousands of euros.
The Alternatives, Ranked
We've tested these in production environments. Here's what actually matters for each one.
Zitadel vs Auth0: The Modern Alternative
RecommendedSwiss-made, open source, and a CNCF member. Zitadel is what Auth0 should have become. It supports OIDC and SAML out of the box, has built-in multi-tenancy (so you can manage multiple organizations from one instance), and runs on a lightweight Go backend. No JVM, no Python runtime. Just a single binary.
What sets Zitadel apart is the managed EU cloud option. If you don't want to self-host, you can run on their European infrastructure with full data residency guarantees. Swiss data protection law is among the strictest in the world, and Zitadel is headquartered in Switzerland. No CLOUD Act exposure.
We're migrating our own infrastructure to Zitadel at Bright Interaction. After running Authentik for over a year, Zitadel's API-first design, better multi-tenant support, and cleaner deployment model won us over.
Pricing
Free self-hosted. Cloud from $100/mo with EU hosting.
Setup difficulty
Moderate. Docker Compose or single binary. Good docs.
Protocols
OIDC, SAML, JWT, API keys
Standout feature
Built-in multi-tenancy with delegated admin
Keycloak vs Auth0: The Enterprise Option
The enterprise standard for self-hosted IAM. Red Hat backs Keycloak, huge community, battle-tested in production at massive scale. If you work in a Java shop or need advanced federation features like identity brokering across multiple external IdPs, Keycloak is hard to beat.
The downside is weight. Keycloak runs on the JVM and needs meaningful resources. Configuration is powerful but complex. Expect to spend time on theming, flow customization, and memory tuning. For smaller teams without Java expertise, this can feel like overkill.
Pricing
Free and open source. Red Hat SSO for paid support.
Setup difficulty
High. Java ecosystem knowledge helps significantly.
Protocols
OIDC, SAML 2.0, LDAP, Kerberos
Standout feature
Identity brokering and user federation
3. Authentik
Python-based with a genuinely excellent admin interface. Authentik is the easiest self-hosted IdP to get running and manage day-to-day. If you're a small team or running a homelab, Authentik gives you a polished experience without the complexity of Keycloak.
We ran Authentik for our own SSO for over a year. It works well. The flow-based authentication system is flexible, and the proxy outpost lets you protect apps that don't natively support SSO. Where it falls short is multi-tenancy and API-first workflows, which is why we're moving to Zitadel.
Pricing
Free and open source. Enterprise support available.
Setup difficulty
Low. Docker Compose, works within an hour.
Protocols
OIDC, SAML 2.0, LDAP, SCIM, proxy auth
Standout feature
Best admin UI of any self-hosted IdP
4. Authelia
Lightweight and focused. Authelia is not a full identity provider. It's an authentication layer that sits in front of your reverse proxy (NGINX, Traefik, Caddy) and protects web applications. If all you need is to add login protection to internal tools, Authelia does this with minimal overhead.
Don't pick Authelia if you need SAML, multi-tenancy, or complex user management. It's a different tool for a different problem. But for what it does, it does well.
Pricing
Free and open source.
Setup difficulty
Low. YAML config, pairs with your existing proxy.
Protocols
OIDC (basic), forward auth headers
Standout feature
Tiny footprint, reverse proxy native
5. Ory
API-first identity infrastructure for developers who want full control. Ory is a suite of Go microservices: Kratos (identity), Hydra (OAuth2/OIDC), Oathkeeper (access proxy), and Keto (permissions). You compose exactly what you need.
This is the most flexible option but also the most demanding. There's no pre-built admin UI. You build your own login pages. The tradeoff is total control over every aspect of your auth flow. Best suited for developer teams building products where identity is a core feature, not just a bolt-on.
Pricing
Free self-hosted. Ory Network cloud from $29/mo.
Setup difficulty
High. Multiple services, developer-oriented.
Protocols
OAuth2, OIDC, custom auth flows
Standout feature
Modular microservice architecture
Comparison Table
| Feature | Auth0 | Zitadel | Keycloak | Authentik |
|---|---|---|---|---|
| Open source | No | Yes (Apache 2.0) | Yes (Apache 2.0) | Yes (custom) |
| Self-hosted | No | Yes | Yes | Yes |
| EU data residency | EU tenant available | Swiss HQ + EU cloud | Self-host in EU | Self-host in EU |
| CLOUD Act exposure | Yes (Okta, US) | No (Swiss) | No (self-hosted) | No (self-hosted) |
| OIDC | Yes | Yes | Yes | Yes |
| SAML | Yes | Yes | Yes | Yes |
| LDAP | Via extension | No | Yes (native) | Yes (outpost) |
| Multi-tenancy | Yes (Organizations) | Yes (built-in) | Yes (realms) | Limited (tenants) |
| Free tier | 7,500 MAU | Unlimited (self-hosted) | Unlimited (self-hosted) | Unlimited (self-hosted) |
| Backend | Proprietary | Go | Java (Quarkus) | Python (Django) |
Why We Chose Zitadel
We ran Authentik in production for our own infrastructure and for client projects. It served us well. But as we took on more multi-tenant projects and needed tighter API integration with our other tools, the gaps became clear.
Zitadel solved the specific problems we kept hitting:
Our recommendation: If you're building a modern application that needs OIDC/SAML with EU data residency, start with Zitadel. If you're in a large Java enterprise needing LDAP and advanced federation, go with Keycloak. If you just need simple SSO for internal tools with minimal setup, Authentik is still excellent.
The GDPR Reality Check
Let's be direct about what GDPR compliance means for identity providers.
Auth0's position
Auth0 offers EU-hosted tenants and has Data Processing Agreements available. They use Standard Contractual Clauses for transatlantic transfers. Legally, they check the boxes. Practically, Okta is a US corporation subject to US law. If a US court or agency issues a subpoena or national security letter, Okta must comply regardless of where the data is physically stored.
Self-hosted position
When you self-host Zitadel, Keycloak, or Authentik on your own EU infrastructure, the data is yours. No third-party processor. No transatlantic legal complications. Your DPA is with your hosting provider, which can be an EU company on EU soil. This is the cleanest GDPR position possible.
Zitadel Cloud position
If you use Zitadel's managed cloud, your data is processed by a Swiss company under Swiss data protection law. Switzerland has an adequacy decision from the EU, meaning data transfers are treated as equivalent to intra-EU transfers. No CLOUD Act, no Schrems II headaches.
Migration Path from Auth0
Switching identity providers is not trivial. Here's a realistic approach:
Run both in parallel
Deploy your target IdP alongside Auth0. Migrate new applications to the new provider while existing ones continue using Auth0. This removes time pressure.
Export user data
Auth0's Management API lets you export users. Passwords cannot be migrated directly (hashes are not exportable), so plan for a password reset flow or use Auth0's automatic migration feature during the transition.
Update application configs
If your apps use OIDC (most modern apps do), migration means changing the issuer URL and client credentials. The protocol is standardized, so the integration code stays largely the same.
Decommission Auth0
Once all applications and users are migrated, shut down the Auth0 tenant. Keep a backup of your Auth0 configuration for reference.
Make the Switch
Auth0 built a great product. But for European businesses in 2026, the combination of US legal exposure, aggressive pricing, and vendor lock-in makes it increasingly hard to justify. Open-source alternatives have caught up in features and surpassed Auth0 in areas that matter for EU compliance.
Zitadel is our pick for modern applications. Keycloak for complex enterprise environments. Authentik for teams wanting the simplest path to self-hosted SSO. All three eliminate the CLOUD Act problem entirely.
We're migrating our own infrastructure to Zitadel. Need help setting up self-hosted identity? We've done this for ourselves and for clients. From planning to deployment to application integration, we can get you off Auth0 and onto something that actually respects EU data sovereignty. Book a free call →