# Mailly vs Senlo: which to pick

> Mailly vs Senlo: compare pricing, platforms, categories, launch weeks, upvotes, awards and founders side by side on ProductsFarm, with notes on which to pick.

Canonical: https://productsfarm.com/compare/mailly-vs-senlo
Last updated: 2026-11-07

|  | [Mailly](https://productsfarm.com/product/mailly) | [Senlo](https://productsfarm.com/product/senlo) |
| --- | --- | --- |
| What it is | Two-way email inboxes for AI agents and applications, with a review step for you | Visual templates and automations for transactional email on your own provider |
| Pricing | Freemium | Freemium |
| Platforms | Web, API, CLI | API, Web |
| Categories | Developer tools, Communication, AI | Developer tools, Communication, Marketing |
| Made for | developers, support teams, product teams | product teams, developers, marketers |
| Built with | [Cloudflare](https://productsfarm.com/tech-stack/cloudflare), [Tailwind CSS](https://productsfarm.com/tech-stack/tailwind-css) | [Next.js](https://productsfarm.com/tech-stack/nextjs), [React](https://productsfarm.com/tech-stack/react), [Umami](https://productsfarm.com/tech-stack/umami), [Tailwind CSS](https://productsfarm.com/tech-stack/tailwind-css) |
| Upvotes | 0 | 0 |
| Website | [mailly.site](https://mailly.site/) | [senlo.io](https://senlo.io/) |

## About Mailly

Mailly is a two-way email service for AI agents and applications. Each inbox gets an address on mailly.site, or a custom domain on a paid plan, and incoming messages, outgoing messages and replies are kept together in one conversation thread. An agent can read the full thread, and a hosted agent can prepare reply drafts that you edit and approve before anything is sent.

The product can be connected through a remote MCP endpoint, an HTTP API, a CLI or SMTP. Inbound mail can be delivered to your own receiver with signed webhooks that are retried on failure. Campaigns handle audience outreach from synced contacts and static or dynamic lists, and Workflows handle lifecycle messages triggered by events, with wait steps. Delivery, bounce, complaint and unsubscribe events are recorded so you can inspect what happened to each message.

Mailly is aimed at developers and teams who want an agent or application to handle email without losing human oversight. Hosted agents currently draft only, so sending from an agent requires your own application to call the API or CLI and apply its own send controls.

## About Senlo

Senlo is a layer on top of the email delivery provider a team already uses, such as Resend, Postmark or any SMTP server. It gives you a visual editor for transactional email templates, with rows, columns, merge tags and conditions, and versions you can roll back to. Templates can be sent through a single API request, and developers receive the same template through the API without writing MJML by hand.

Lifecycle automations start from events sent to the API, such as a new contact being added. An automation can send an email, wait, check your own API whether a user did something, and then take a different path. Each node shows how many contacts are in it. Sends, deliveries, bounces and engagement are shown per workspace, with a live feed of failures and a suppression list. Senlo renders, personalises, tracks and decides, then hands each message to the provider you chose, so switching providers does not require editing templates.

The product suits teams that send transactional email and onboarding sequences and want editors who do not write code to work on them. It can be self-hosted with Docker Compose under the AGPL-3.0 license, or used as a hosted service with a free plan for one person, and paid plans that add members, roles and audit logs.

## Related

- [Mailly](https://productsfarm.com/product/mailly)
- [Senlo](https://productsfarm.com/product/senlo)
- [More comparisons](https://productsfarm.com/compare)