Topol.io Launches Transactional Email Platform: Lettr

Nearly every business needs to send transactional emails, such as account verifications, password resets, and subscription changes. In theory, these emails are simple to manage, but the developers responsible for them often run into two limitations.

First, the customer-facing parts of the emails, like tracked links and hosted assets, live on shared vendor domains, whose reputations and defaults the developers do not control.

Second, the email templates themselves are only editable via code, turning copy and design updates into developer tickets from marketing and product teams.

Lettr solves both of these problems and more.

With Lettr, development teams can use their own domains for sending, tracking, inbound replies, and asset storage, which helps keep emails on-brand and allows more in-house control over email deliverability.

This is an uncommon offering among transactional email platforms, because it requires mature infrastructure for DNS setup, routing, and certificate management. Lettr can support this capability because it's built on the enterprise-grade email infrastructure of Ecomail, maker of an email platform serving over 12,000 organizations, which has spent the last 12 years building systems that make these domain configurations practical and affordable.

For the same reason, Lettr is able to offer dedicated IP pools and custom rate limits for high-volume enterprise senders that need even more control over their setup.

For marketers and product owners, Lettr enables full control over templates, drafts, publishing, and versioning via Topol's intuitive, drag-and-drop email editor, which is used by over 40,000 companies. The result is that once developers implement trigger conditions, non-developer teams can take full control of the email content without needing to bother the devs.

Lettr bridges the gap between the concerns of developers and marketers over transactional email.

Lettr is designed to make migration from other transactional email tools straightforward. Teams can switch providers with minimal changes, keep existing templates (including HTML output generated by React Email), and move template edits into Lettr’s versioned workflow. For Laravel teams already sending transactional email, Lettr can be integrated with a one-command setup.

Other notable features for developers include event webhooks for accepted, delivered, delayed, bounced, opened, clicked, and spam events, 90-day API logs for troubleshooting, and optional type-safe mail objects that help teams keep templates and code in sync.

Lettr can be managed via our UI or an API.

Notable features for marketers include a template library for common transactional emails, easy multilingual template management, dynamic placeholders, and a full lifecycle analytics suite.

Another important feature, which is rare in transactional email editors, is synced sections, which allows teams to update a master section once and automatically apply changes to all templates where that section is used.

The Lettr platform is focused purely on transactional email, and does not offer bulk sending capability or contact list imports.

Lettr is the latest standalone product to emerge from the Ecomail ecosystem, following Topol, which spun out from Ecomail at the end of 2025, and DMARCeye—a guidance-based DMARC monitoring and reporting platform.

Together, Lettr, DMARCeye, Topol, and Ecomail comprise the first stage of Big Good: an Ecomail-led ecosystem of tools designed for marketing professionals and developers working across email communication, content, security, and design. Additional tools are in development and will soon be released under the Big Good umbrella.

For more information about Lettr, visit lettr.com.