Lucia vs Supabase Auth
Lucia and Supabase Auth both answer the same question: how do users sign in? No longer a library but a reference that teaches you to implement sessions yourself, with code you copy and own. Auth that ships inside Supabase, with users stored in your Postgres and row level security wired to the session. Supabase Auth covers more of the ecosystem, so it survives a change of framework; Lucia is the better fit while you stay where it is strongest.
Verdict
Supabase Auth covers more of the ecosystem, so it survives a change of framework; Lucia is the better fit while you stay where it is strongest.
Pick Lucia if
- ✓You end up understanding exactly how your session cookies and tokens work.
- ✓Zero dependency to break, deprecate or change licence underneath you.
- ✓Session schema is yours, so it fits whatever data model you already have.
Pick Supabase Auth if
- ✓The user table is a Postgres table, so foreign keys to it just work.
- ✓Row level security policies read the session directly, pushing authorization into the database.
- ✓One vendor for auth, storage and database keeps the moving parts low.
| Comparison | Lucia | Supabase Auth |
|---|---|---|
| Pricing shape | Free. It is documentation, so there is nothing to buy or subscribe to. | Included with the Supabase project you already pay for, with additional cost only at higher active-user tiers. |
| Frameworks | Next.js, SvelteKit | Next.js, SvelteKit, Nuxt, React Native, Expo, Flutter |
| In one line | No longer a library but a reference that teaches you to implement sessions yourself, with code you copy and own. | Auth that ships inside Supabase, with users stored in your Postgres and row level security wired to the session. |
Pricing described qualitatively because published plans change often. Checked 2026-08-23. Confirm current terms on Lucia and Supabase Auth.
Lucia
Strengths
- ✓You end up understanding exactly how your session cookies and tokens work.
- ✓Zero dependency to break, deprecate or change licence underneath you.
- ✓Session schema is yours, so it fits whatever data model you already have.
- ✓Excellent teaching material even if you eventually pick a different tool.
Tradeoffs
- ✗Copied code means you carry the maintenance and security review forever.
- ✗No package upgrades, so fixes only land if you go looking for them.
- ✗Every provider, reset flow and rate limit is hand-rolled work.
- ✗Hard to justify on a team where nobody wants to own auth internals.
Supabase Auth
Strengths
- ✓The user table is a Postgres table, so foreign keys to it just work.
- ✓Row level security policies read the session directly, pushing authorization into the database.
- ✓One vendor for auth, storage and database keeps the moving parts low.
- ✓Client libraries for web and mobile share the same session model.
Tradeoffs
- ✗Bundled with Supabase, so adopting it usually means adopting the whole platform.
- ✗Auth schema lives in a managed namespace you cannot freely reshape.
- ✗Row level security is powerful but easy to get subtly wrong.
- ✗Self-hosting the full stack to escape the cloud is a real operations project.
Same pair, different context
Frequently asked questions
Is Lucia or Supabase Auth better?
Neither is better in the abstract. Supabase Auth covers more of the ecosystem, so it survives a change of framework; Lucia is the better fit while you stay where it is strongest. The wrong choice here is usually recoverable, so weight speed of decision over certainty.
What is the main drawback of Lucia?
Copied code means you carry the maintenance and security review forever. No package upgrades, so fixes only land if you go looking for them.
What is the main drawback of Supabase Auth?
Bundled with Supabase, so adopting it usually means adopting the whole platform. Auth schema lives in a managed namespace you cannot freely reshape.
Can you switch from one to the other later?
Usually, at a cost that grows with how much of your product leans on the authentication layer. The sooner you wrap it in your own interface, the cheaper the exit stays.