Lettera alternatives

Tools that do what Lettera does, found by what they say they do rather than by shelf. Among the equally alike, the most used come first. Each line says how it differs from Lettera.

Read 2026-10-26 · Lettera itself: Free

With a free plan or free to use: AI Email API & Infrastructure for AI Agents, Robotomail, mcpemails, OpenClaw, e2a, Prefactor.

10 alternativesUnlike Lettera

#1
AI Email API & Infrastructure for AI Agents Agents MCP · sign-in
Gives an agent its own email address, sending and receiving mail through an API, with replies scored for prompt injection.
More widely used
105
Active
From $20/mo
#2
Robotomail Agents
Provides real email addresses and mailboxes for AI agents to send and receive messages via API.
More widely used
464
Active
From $19/mo
#3
Mailbuttons Agents MCP · open
Runs single-job AI agents on their own email addresses, drafting quotes and replies that wait for approval before sending.
Also: Workflow automation
Little sign of use
Active
From ≈ $199/mo
#4
PolyAI Agents
Builds and runs voice AI agents that handle customer conversations across phone, chat, and other channels.
Also: VoiceMore widely used
392k
Active
Pay per use
2017
#5
mcpemails Agents MCP · sign-in
Gives AI agents live read, search and send access to Gmail, Outlook and IMAP mailboxes through an MCP endpoint.
Same job
14
Active
From $7.20/mo
#6
OpenClaw Agents MCP · sign-in
Open source AI assistant that manages email, calendar, and tasks from chat apps without subscriptions.
Open sourceAlso: Chat assistant
182k
Active
Open source
#7
Gumloop Agents
Builds and deploys autonomous agents that automate business tasks like sales pipeline management, prospect research, and CRM updates.
Also: Workflow automationMore widely used
372k
Active
From $37/mo
#8
e2a Developer tools MCP · sign-in
Sends transactional email over HTTP or SDKs and gives AI agents two-way inboxes with threading, webhooks, and human approval of outbound messages.
Open sourceMore widely used
1
Active
Open source
#9
Prefactor Agents
Evaluates and monitors AI agent runs in production, catching failures and enforcing policies at runtime.
Also: Monitoring, EvaluationMore widely used
550
Active
From $499/yr
2024
#10
Lindy Agents
Executes tasks across connected tools like email, Slack, and CRM by learning your workflows and operating on a schedule.
Also: Workflow automationMore widely used
153k
Active
From $49.99/user/mo

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How this list is made: the words Lettera is described with (what it does, for whom, what it is used for) are matched against every tool in the Atlas. A tool on the same shelf, or doing the same kind of work, counts for a little more. Nothing here is paid for.