Helo

Transactional and marketing email from applications goes through Helo's API and SMTP service, with account mail such as password resets and receipts kept apart from promotional sends. The design keeps the two lanes separate, so a bulk campaign cannot slow down a password reset, and the team says deliverability is its first priority. Applications can send by calling the API or by connecting over SMTP, and the team states that setup takes minutes.

The feature set includes detailed analytics, unlimited webhooks, unlimited users and unlimited sending domains. The service is offered on one plan, billed as a small monthly platform fee plus a charge for each email, with a free allowance for testing. The pricing page includes a calculator that compares the bill with other email services at different volumes.

Sending on behalf of other businesses

Platforms that send email for their own customers face harder problems, and Helo supports multi-tenant environments for them. Each of a platform's customers can have fully isolated sending, so one abusive account cannot damage the sender reputation that the rest rely on, and customers can send from their own domains. The product is built to catch bad senders early, so a single spammy customer does not wreck a shared reputation and then need fixing again and again.

A small team with a shared background

The product was introduced on Hacker News on 1 October 2026 by a co-founder. Most of its members, the team reports, spent years together at Postmark, the transactional email provider. The company is bootstrapped, with no outside investors, and its About material places team members across North America, Germany and Japan. It describes itself as intentionally lean and independent, with a focus on one product: a modern email API that developers enjoy using at an affordable price.