# Supabase Auth: Email address not authorized
> Supabase sign-up emails fail with Email address not authorized because the default SMTP only sends to your team. Set up custom SMTP before launch.
Canonical: https://app369.com/fix/supabase-email-address-not-authorized/
Last updated: 2026-11-09
Email address not authorized (email_address_not_authorized) means the project still sends auth email through Supabase’s default SMTP service. That service only delivers to members of your Supabase organization, so sign-up works for you and fails for customers.
**Short answer**
Set up a custom SMTP provider in the Auth settings, with the host, port, user, password and a From address from your email service. After that, confirmation, magic link and reset emails go to any address. For a quick test before then, add the tester to the organization’s team.
Rather not fix it yourself? [**App Fix Ticket**](https://app369.com/fixed-price/flutter-firebase-bug-fix/) starts with a fixed-price diagnosis, then a fixed price for the fix before any fix work.
## **Why the email is refused, and the fix**
1. 01 ### **The project uses the default SMTP service**
> “Email sending is not allowed for this address as your project is using the default SMTP service. Emails can only be sent to members in your Supabase organization.” [**Supabase docs, Auth error codes (email_address_not_authorized)**](https://supabase.com/docs/guides/auth/debugging/error-codes) Supabase gives every project a starter email server for testing templates. It refuses any address outside the organization’s team, which is why your own sign-up works and a customer’s doesn’t.
2. 02 ### **Custom SMTP was never set up for launch**
> “This server imposes a few important restrictions and is not meant for production use.” [**Supabase docs, Send emails with custom SMTP**](https://supabase.com/docs/guides/auth/auth-smtp) Pick an email service that supports SMTP, verify your sending domain there, and enter its SMTP settings in the project’s Auth settings. Supabase names services such as Resend and AWS SES as working options.
3. 03 ### **A tester is not on the team**
> “Unless you configure a custom SMTP server for your project, Supabase Auth will refuse to deliver messages to addresses that are not part of the project's team.” [**Supabase docs, Send emails with custom SMTP**](https://supabase.com/docs/guides/auth/auth-smtp) Before custom SMTP is live, only team members get email. Invite the tester in the Team tab of the organization settings, or wait until SMTP is set up.
4. 04 ### **The rate limit hits next** Also check: the default service also limits sending, currently 2 messages per hour. Once custom SMTP is saved, Supabase starts the project at 30 messages per hour, which you can raise on the Rate Limits page.
Checked against the vendor’s docs on November 9, 2026: [Supabase docs: Auth error codes](https://supabase.com/docs/guides/auth/debugging/error-codes); [Supabase docs: Send emails with custom SMTP](https://supabase.com/docs/guides/auth/auth-smtp).
## **Rather hand it over?**
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- [from $450**App Fix Ticket**One reproducible bug in an existing mobile or web app, diagnosed and fixed.**See scope and start**](https://app369.com/fixed-price/flutter-firebase-bug-fix/)
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Related: [**Supabase Email address invalid**](https://app369.com/fix/supabase-email-address-invalid/) · [**Supabase email rate limit exceeded**](https://app369.com/fix/supabase-email-rate-limit-exceeded/) · [**Supabase auth emails going to spam**](https://app369.com/fix/supabase-auth-emails-going-to-spam/) · [**Supabase Email not confirmed**](https://app369.com/fix/supabase-email-not-confirmed/)
Questions
## **More on this error**
**Why does sign-up work for me but not for customers? **+
Your address is on the Supabase organization’s team, so the default SMTP service delivers to it. Customers are not, so their emails are refused until custom SMTP is set up.
**Is it the same as Email address invalid? **+
No. Email address invalid means Supabase refused the address itself, such as a test domain; not authorized means the address is fine and the default email service won’t send to it.
**Can you fix it for me? **+
If one bug is the whole problem, the App Fix Ticket covers it: a written diagnosis first, then the fix. If the app has more going on, the Launch Check is a written check of the whole app. Each issue found is rated critical, high, medium or low, with where it is and how it was confirmed. No issues worth fixing, no charge. If the Launch Check finds nothing rated medium or higher, Simon refunds the full $450. You keep the report either way. This applies to the first 10 Launch Checks bought after October 30, 2026.
A different error?
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