Sendfeather

Transactional email for product teams: send receipts, OTP codes and notifications over SMTP or one API call, and see every message's delivery timeline. Paid plans include hosted mailboxes for your domain. $7 for 10,000 emails/month, $15 for 50,000, $29 for 100,000, with metered overage instead of hard pauses. Free plan: 1,000/month, no card. WordPress plugin and MCP server included.