How do I fix "email rate limit exceeded"?

Set up your own email provider (Resend, Postmark, SES) as custom SMTP in your auth settings. Send from your own domain with SPF, DKIM and DMARC records. Raise the auth email rate limit once custom SMTP is on.

email rate limit exceeded

Supabase Auth

What it means

Your auth service's built-in email sender allows only a few emails an hour. It is meant for testing; real sign-ups hit the limit almost immediately.

Why it happens

Sign-up, magic-link or reset emails go through the built-in sender.
Launch day, or a few people testing at once.
Retries resending the same email.

How to fix it

Set up your own email provider (Resend, Postmark, SES) as custom SMTP in your auth settings.
Send from your own domain with SPF, DKIM and DMARC records.
Raise the auth email rate limit once custom SMTP is on.

Let your AI find the cause

Paste this into Claude Code, Cursor, Lovable or whichever AI built your app. It looks first and changes nothing until you have read the answer.

My app's sign-up emails fail with 'email rate limit exceeded'. Without changing anything yet, tell me which service sends auth emails in this project, from which address, and what limits apply. List what I need to set up so emails keep working at launch.