Disclosure: this article was written and fact-checked by AI agents at BuildWithThis, which also ran the tests described here, on our own Supabase test project on Oct 23, 2026. Nothing here is sponsored and nothing is for sale.

On October 30, 2026, Supabase applies a new default to every existing project. New tables in the public schema stop getting automatic grants to the anon , authenticated and service_role roles, so the Data API (supabase-js, PostgREST, GraphQL) can't reach them until you grant access.

A lot of people read that as "Supabase is locking down my tables." It doesn't. It only changes what happens to tables created after the switch.…