Common Supabase RLS Errors and How to Fix Them

Introduction — Understanding Common Supabase RLS Errors

If you’re building an authenticated application, you’ll eventually face common Supabase RLS errors—especially once Row Level Security is enabled. These errors can appear without clear explanations and often sound more cryptic than logical.

Examples include:

  • “new row violates row-level security policy”
  • “no insert policy exists for table”
  • “permission denied for table”
  • “null value violates RLS check constraint”

This guide breaks down the most common Supabase RLS errors, explains why they happen, and teaches you exactly how to fix them—whether you’re coding manually or using AI tools like Lovable, Bolt.new, v0, Cursor, or PromptXL.

Why Supabase Row Level Security Problems Happen

Supabase treats security as the default state.

Once RLS is enabled:

Nothing can be read, inserted, updated, or deleted until policies explicitly allow it.

That means:

  • Your code may look correct
  • Your API request may receive data
  • Your UI may appear functional

…but Supabase will still reject access unless permissions match the rules.

Understanding the root cause of common Supabase RLS errors means checking:

  1. Authentication
  2. Ownership structure
  3. API key type
  4. CRUD-specific policies

Once you treat RLS like a predictable system rather than guesswork, errors become easy to resolve.

Error #1 — “new row violates row-level security policy”

What it means:

Supabase is blocking the INSERT because no valid INSERT policy exists—or the row does not satisfy it.

Common causes:

  • Missing user_id column
  • Insert policy missing WITH CHECK
  • Incorrect column reference

Fix:

create policy "Insert own rows"
on your_table
for insert
with check (user_id = auth.uid());

Error #2 — No Insert RLS Policy in Supabase

What it means:

Supabase is simply telling you:
➡️ There is no INSERT policy at all.

Fix:

Add an INSERT policy:

create policy "Allow insert"
on your_table
for insert
with check (true);

Tip: Change true to proper ownership rules later.

Error #3 — Permission Denied Because of Missing RLS Access Rules

Cause:

You attempted an operation with no matching policy.

How to fix:

Ensure policies exist for every action your app performs:

ActionNeeds Policy
SELECTYes
INSERTYes
UPDATEYes
DELETEYes

Error #4 — SELECT Blocked by Supabase RLS

Cause:

Your SELECT policy exists but returns false.

Fix:

create policy "Read own rows"
on your_table
for select
using (user_id = auth.uid());

Error #5 — RLS Fails Because user_id Is Missing

Cause:

Supabase attempted an INSERT where user_id was NULL.

Fix:

  1. Ensure the user is logged in:
select auth.uid();
  1. Set user_id automatically:
const { data } = await supabase
  .from("tasks")
  .insert({
    title: "Example",
    user_id: user.id // required
  });

Error #6 — RLS Enabled With No Supporting Policies

Cause:

Table is fully locked.

Fix:

Create a policy:

alter table your_table enable row level security;
create policy "Open access" on your_table for all using (true);

Only use this temporarily.

Error #7 — App Requests Blocked, Dashboard Requests Allowed

Cause:

Using service_role in Dashboard and anon in the app.

Fix:

Use an authenticated or service role only on backend—never on frontend.

Error #8 — Multi-Tenant Access Issues in Supabase RLS

Cause:

Incorrect organization_id or membership logic.

Fix:

For multi-tenant logic:

using (
  organization_id in (
    select organization_id from memberships where user_id = auth.uid()
  )
)

How to Prevent Future Supabase RLS Errors

Follow this workflow:

  1. Build your schema first
  2. Add ownership fields
  3. Enable RLS
  4. Write correct policies
  5. Test with multiple user accounts
  6. Use the policy simulator
  7. Scale with multi-tenant logic

This approach eliminates guesswork and prevents the most common Supabase RLS errors before they occur.

Summary — Fixing Common Supabase RLS Problems Successfully

To recap, the most common mistakes come from missing:

  • authentication
  • ownership columns
  • matching policies
  • correct key usage
  • CRUD-specific rules

Once you understand these patterns, fixing common Supabase RLS errors becomes straightforward.

Avoid RLS Errors Completely — Use PromptXL

If you want to avoid RLS headaches entirely, PromptXL builds Supabase apps with working RLS from the beginning.

You get:

  • ✔ Automatic ownership mapping
  • ✔ Correct CRUD policies
  • ✔ Multi-tenant support
  • ✔ Secure-by-default schemas
  • ✔ AI models trained specifically for Supabase

No more broken CRUD | more unexplained errors | No more wasted debugging time

🚀 Build confidently

🔐 Ship securely

⚡ Scale without friction

👉 Try PromptXL — the fastest way to build secure Supabase apps.