Transactional email

The current best-in-class for indie SaaS. React Email integration, clean dashboard, no setup hell. The free tier covers most early-stage SaaS.

Best deliverability in the industry. More expensive at scale than Resend but every email actually arrives, including the password reset to your most paranoid user.

Twilio-owned. Bigger surface, more features, also more clunk. Use if you need their templating UI or are already on Twilio.

Cheapest at scale by an order of magnitude. Worst onboarding experience: sandbox mode, deliverability tickets, IP warm-up. Only worth it once you're sending tens of thousands per day.