postgres role lacks ownership of auth.users, cannot CREATE TRIGGER (Error 42501)

[kairi717]

Hello Supabase Community,

I'm trying to automatically create a user profile in a public.profiles table whenever a new user signs up. The recommended way to do this is by using a database trigger on the auth.users table.

The Problem

However, when I try to create the trigger, I get the following error:

ERROR: 42501: must be owner of table users

This indicates that the postgres role does not have ownership of the auth.users table.

What I've Already Tried

I've followed the standard workarounds for this issue, but they also fail with permission errors:

Attempting to disable RLS first:

SQL

ALTER TABLE auth.users DISABLE ROW LEVEL SECURITY;

This fails with the same error: ERROR: 42501: must be owner of table users.

Attempting to grant admin privileges:

SQL

GRANT supabase_auth_admin TO postgres;

This fails with a different error: ERROR: 42501: "supabase_auth_admin" role memberships are reserved, only superusers can grant them.

This suggests that the postgres role in my project is not a superuser and has non-standard, restricted permissions. As I am on the free plan, I cannot open a support ticket.

My Question

Is it possible that the permissions for the postgres role in my project (Ref: cxfweuxedwyxmouvjxis) are misconfigured?

Is there a way to reset the postgres role's permissions to the default state for a free-tier project?

Is there an alternative method to reliably create a user profile upon signup that does not require creating a trigger on auth.users?

Relevant Code

Here is the function and trigger I am trying to create:

SQL

-- The function to create a profile

CREATE OR REPLACE FUNCTION public.handle_new_user()
RETURNS TRIGGER AS $$
BEGIN
  INSERT INTO public.profiles (user_id, nickname, picture_url, email)
  VALUES (
    new.id,
    new.user_metadata->>'full_name',
    new.user_metadata->>'avatar_url',
    new.email
  )
  ON CONFLICT (user_id) DO UPDATE SET
    nickname = new.user_metadata->>'full_name',
    picture_url = new.user_metadata->>'avatar_url',
    email = new.email;
  RETURN new;
END;
$$ LANGUAGE plpgsql SECURITY DEFINER;

-- The trigger that fails to be created

CREATE TRIGGER on_auth_user_created
  AFTER INSERT ON auth.users
  FOR EACH ROW EXECUTE PROCEDURE public.handle_new_user();

Any help or insight on how to resolve this permission issue would be greatly appreciated. Thank you!

[Labaybat]

Summary of the Issue:
On Supabase free tier, you cannot create triggers directly on the table because you don’t have ownership or superuser privileges. This is a platform restriction, not a misconfiguration.

Solutions:

Recommended Alternative: Use Supabase Edge Functions or Client-side Logic

Instead of a database trigger, use a Supabase Edge Function or your backend/frontend app to create a profile after user signup.
Example: After a user signs up, call a function (serverless or client-side) that inserts a row into public.profiles using the new user’s ID and metadata.

Automate with Supabase Auth Hooks (if available)

Supabase now supports “Auth Hooks” (beta/paid plans) for post-signup actions. On free tier, this may not be available, so fallback to client/server logic.

Why Triggers Fail

The error is expected: you don’t have ownership of and cannot disable RLS or grant roles.
There is no way to reset permissions or gain superuser access on free-tier Supabase.
Example Client-side Solution (JavaScript/TypeScript):
// After user signs up
const { user } = await supabase.auth.signUp({ email, password, ... });
if (user) {
await supabase.from('profiles').upsert({
user_id: user.id,
nickname: user.user_metadata.full_name,
picture_url: user.user_metadata.avatar_url,
email: user.email
});
}

You cannot create triggers on [auth.users] in Supabase free tier due to platform restrictions.
Use client-side or server-side logic to create a profile after signup.
No way to reset or elevate permissions on free tier.
Your SQL function is correct, but the trigger must be attached to a table you own (not [auth.users])

[kairi717]

Thank you so much for your help. I genuinely appreciate the time and effort you put into resolving my issue. Your support made a real difference

[GaryAustin1]

You can indeed add triggers to auth.users using the SQL editor.
You cannot add functions, change tables (enable RLS), add columns, indexes and more.
But triggers are allowed and in fact called out in the User Management guides to auto populate profile tables.

[GaryAustin1]

No issues on a default instance.

Make sure you check that you are postgres role at the bottom right.

[kairi717]

Thanks so much, I'll definitely try it out

[kairi717]

I was able to solve my problem thanks to the comments above and the links below. Thanks to everyone
https://github.com/orgs/supabase/discussions/34270#discussioncomment-13210788