Supabase email templates: customize per email type and test the variables before launch

TL;DR

Use the documented template variables for the action link in each template. Set the sender name and confirm the from address.

Steps

1. Auth emails (confirmation, magic link, recovery, invite) come from default templates with Supabase branding. Agents leave them until launch day, when fixing them means resending flows under pressure.
2. In the dashboard go to Authentication, Email Templates. There is one template per email type: confirmation, magic link, recovery, invite, and others. Customize each one you use, not just signup.
3. Use the documented template variables for the action link in each template. Hardcoding a URL instead of the variable breaks when the Site URL changes between environments.
4. Set the sender name and confirm the from address. The default sender is fine for dev and wrong for production trust.
5. Keep the emails short and single-purpose. One link, one action. Agents love adding marketing copy to transactional auth emails; it hurts deliverability.
6. Send a real test email for each template type and click the link. Confirm it lands on your app, completes the action, and the session is established.

When to use

You are seeing this: Auth emails (confirmation, magic link, recovery, invite) come from default templates with Supabase branding. Use this skill when you run into "Supabase email templates: customize per email type and test the variables before launch".

When not to use

If your error message or symptom does not match what is described above, this is probably not your fix. Search for your exact error text instead of forcing this one to fit.

Versions

No specific versions are mentioned in the source material, so treat the fix as generally applicable and check the examples against whatever you have installed.

Why this happens

The original report does not dig into a root cause. It documents the symptom and the fix that resolved it.

Verified against live Supabase docs 2026-09-26: https://supabase.com/docs/guides/auth/auth-smtp