Email infrastructure · plans & pricing
5 providers · USD monthly pricing · editorial picks, not delivery-score rankings
Agent-oriented email services expose inbox creation, receiving, threading, and events as programmable primitives. They suit software that needs an email identity and two-way conversations rather than only outbound notifications.
Agent email identity
Programmable inboxes and message processing suit software agents that need their own two-way email workflow.
Free access / trial
Developer access varies
Detailed plan allowances are not available in the tracked catalog. Compare current inboxes-based plans on the provider page.
Volume quote unavailable
Check inboxes-based pricing and plan limits
Conversation workflows
Multi-tenant inboxes, event streaming and conversation threads fit applications managing separate automated identities.
10 inboxes included
Custom terms
Custom terms
Custom terms
Custom terms
Volume quote unavailable
Check inboxes-based pricing and plan limits
Inbound building blocks
Inbound routing can provide an alternative foundation when a team wants to build its own agent conversation layer.
3,000 emails included · 100/day cap
10K emails included
50K emails included
100K emails included
$35/mo
Foundation at 50K emails
Monthly email volume
50Kemails / month
Plan matches use included monthly email allowances, then eligible overages. Daily caps still apply. Contact-, seat- and inbox-based subscriptions cannot be matched from sends alone. Estimates exclude taxes and optional add-ons.
Compare the full directory
| Matched plan / billing | |||
|---|---|---|---|
| MailgunSinch | Email validation · Inbound routing · EU region | Foundation50K emails included | $35/moPricing details |
| PlunkPlunk | Open source · Simple API · AWS SES infrastructure | Standard3,000 emails included | $47/moPricing details |
| MailerooMaileroo | Transactional API · Inbound webhooks · Simple REST setup | Standard10K emails included | $42/moPricing details |
| AgentMailAgentMail | AI agent inboxes · Programmatic email · Message processing | Billed by inboxesDetailed plans not available | —Pricing details |
| RobotomailRobotomail | Multi-tenant inboxes · Event streaming · Conversation threads | Billed by inboxesSee provider plan details | —Pricing details |
Send estimates use the same tracked plans as each provider’s pricing page. “—” means a comparable send-based quote is unavailable, not that sending is free.
The buying guide
An email agent needs an address, inbound messages and a conversation model. An outbound-only API may not provide those building blocks.
Explore pricing: AgentMailRobotomailMailgun
Incoming messages and attachments are untrusted input. A message should not be able to authorize an agent to reveal secrets or take privileged actions.
Agent products may bill for inboxes rather than raw sends. Plan around how many identities you create and how much traffic each one receives.
Explore pricing: RobotomailPlunk
An agent-oriented API exposes receiving and inbox primitives for two-way workflows. A sending API primarily delivers outbound notifications. Compare inbox creation, threading and inbound events for your use case.
The number of inboxes does not establish how many messages a subscription allows. The comparison keeps inbox-based pricing separate and only matches published email-send plans to the volume slider.
No. Incoming content is untrusted input. Restrict agent permissions, verify event authenticity and require human approval for sensitive actions rather than allowing an email to grant authority.