Supabase Auth vs Firebase Auth — which auth service wins for your brief, in 2026
Two auth services, side by side. Supabase Auth is postgres-native auth bundled with supabase. free, owned-data, integrates with rls. Firebase Auth is google's bundled auth — email, social, phone, anonymous. generous free tier, locks you into google. The verdict, the criteria, and the honest take below.
ALL AUTH COMPARISONS →Verdict in one paragraph
The two bundled-with-platform default options. Supabase Auth wins for Postgres-aligned apps and teams that want SQL ownership. Firebase Auth wins for Google-platform apps and teams already on Firebase services. For greenfield projects in 2026, Supabase tends to win on architectural openness; Firebase tends to win where the broader Google-cloud lock-in is acceptable.
Score across the criteria: Supabase Auth 3 · Firebase Auth 3
Side by side
Decision criteria
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Which is the right pick for SQL / Postgres-stack apps?
Supabase Auth
Native Postgres integration with auth.uid() in RLS policies. The Supabase Auth answer.
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Which is the right pick for Firebase / Google-Cloud stack?
Firebase Auth
Tight integration with Firestore, Functions, FCM. The natural fit.
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Which has the lower long-term lock-in?
Supabase Auth
Built on GoTrue, Apache-licensed, self-hostable. Firebase is fully proprietary.
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Which has the better free tier?
Firebase Auth
Firebase Auth free tier (50k MAUs) is more generous on the headline number. Supabase Auth is free as part of the Supabase free tier across all services.
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Which has the better SQL / RLS story?
Supabase Auth
Native by design. Firebase Auth + Firestore is a different data model.
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Which has the better mobile SDK?
Firebase Auth
Firebase's mobile SDKs are mature and battle-tested. Supabase mobile SDKs are good but younger.
What Supabase Auth is best for
- Apps already on Supabase where auth is one of several services
- Teams that want to own the user database
- Postgres + RLS workloads where auth.uid() is the policy primitive
- Cost-sensitive teams at any scale
Read the full Supabase Auth entry: /authentication/supabase-auth/
What Firebase Auth is best for
- Firebase-stack apps using Firestore / Cloud Functions / FCM
- Mobile apps where Firebase SDK is the path of least resistance
- Cost-sensitive products at sub-50k MAU scale
Read the full Firebase Auth entry: /authentication/firebase-auth/
The auth choice is the easy half — your migration is the hard one
The hard half is migrating user accounts off the old stack without breaking sessions, getting your team adopted, and surviving the SOC2 / HIPAA audit conversations. The 30-min call covers all three for your specific project — describe your stack, your scale, your compliance constraints; I tell you whether Supabase Auth or Firebase Auth (or something else) is your fit.