Lovable email not sending — fix Supabase Auth emails and SMTP
Lovable email not sending — fix Supabase Auth emails and SMTP
Lovable uses Supabase Auth for user management. Supabase’s built-in email has a 3 emails/hourlimit on the free tier — enough for testing, not production. Transactional emails (password reset, magic links, email confirmation) must be routed through a real SMTP provider (Resend, SendGrid, Postmark) for production apps.
Quick fix for Lovable email not sending — fix
Fix 1 — Set up a custom SMTP provider
In Supabase Dashboard → Authentication → SMTP Settings: enable Custom SMTP. Use Resend (free tier: 3,000 emails/month): sign up at resend.com, add your domain, get SMTP credentials. Set: Host = smtp.resend.com, Port = 465, Username = resend, Password = your_api_key.
Deeper fixes when the quick fix fails
- 02
Fix 2 — Authenticate your email domain
Your SMTP provider requires you to add DNS records to prove you own the domain. In Resend → Domains: add your domain and copy the DNS records (TXT for SPF, CNAME for DKIM). Add these at your registrar. Without domain authentication, emails land in spam even with custom SMTP.
- 03
Fix 3 — Configure email templates
In Supabase Dashboard → Authentication → Email Templates: update the From Address to use your authenticated domain (e.g.,
noreply@yourdomain.com). Update the template body to include your app name and brand. The confirmation URL must use your production domain, not Supabase’s default URL. - 04
Fix 4 — Test the full email flow
Sign up with a real email address (use a service like Mailinator for testing). Check: (1) confirmation email arrives, (2) link works and confirms the account, (3) password reset email arrives within 60 seconds, (4) emails land in inbox not spam. If any fail, check Supabase Auth logs for error details.
Verify deliverability
Send a test email to a Gmail address and a Microsoft/Outlook address. Open the message and inspect headers — you should see SPF: pass and DKIM: pass. If either says fail or neutral, your DNS records haven’t propagated or are typed incorrectly. Tools like mail-tester.com give a deliverability score out of 10.
Why AI-built apps hit Lovable email not sending — fix
Supabase Auth emails use Supabase’s shared email infrastructure by default. For production: rate limits kick in, emails land in spam (no custom domain authentication), and you can’t customise the from address.
The shared infrastructure is rate-limited to 3 emails per hour, sends from noreply@mail.app.supabase.io, and doesn’t have SPF/DKIM on your domain — all three of which cause Gmail and Outlook to spam-foldering your messages.
“My users say they never get the password reset email.”
Diagnose Lovable email not sending — fix by failure mode
Match your symptom to the fix before touching Supabase.
| Symptom | Cause | Fix |
|---|---|---|
| No emails arrive at all after N requests | Supabase default SMTP rate-limit (3/hour) | Fix 1 |
| Emails arrive but land in spam / Promotions | No SPF/DKIM on your sending domain | Fix 2 |
| Email arrives but link goes to localhost or preview URL | Site URL / redirect URL wrong in Supabase Auth | Fix 3 |
Related errors we fix
Still stuck with Lovable email not sending — fix?
If your users aren’t receiving email and you can’t figure out which layer is broken, we fix the full chain:
- →Users say they never get confirmation / password reset email
- →Emails arrive but land in spam
- →You're hitting Supabase's 3/hour rate limit
- →You want your emails branded from your own domain
Lovable email not sending — fix questions
Why is the Supabase default email not enough for production?+
What's the best SMTP provider for a Lovable app?+
How do I know if SPF and DKIM are configured correctly?+
My password reset email links to localhost. How do I fix it?+
How many emails can I send for free on Resend/SendGrid/Postmark?+
Can someone set this up for me?+
Ship the fix. Keep the fix.
Emergency Triage restores service in 48 hours. Break the Fix Loop rebuilds CI so this error cannot ship again.
Hyder Shah leads Afterbuild Labs, shipping production rescues for apps built in Lovable, Bolt.new, Cursor, Replit, v0, and Base44. our rescue methodology.
Lovable email not sending — fix experts
If this problem keeps coming back, you probably need ongoing expertise in the underlying stack.