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An inbox is a unique email address assigned to an agent. When you create an inbox, the agent can immediately send and receive email from that address.

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Address format

Inboxes use the openmail.sh domain: 
{mailboxName}@openmail.sh
For example: support@openmail.sh
  • If you provide a mailboxName, it becomes the local part of the address
  • If you omit it, we generate a random 8-character alphanumeric string
  • Mailbox names must be 3–30 characters, lowercase alphanumeric with dots and hyphens allowed
Need your own domain (e.g. agent@yourdomain.com)? See Custom domains.

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Sender name

Set displayName when creating or updating an inbox to control how recipients see the sender. Without a display name, recipients see the raw email address. With a display name, the From header becomes Name <address>. 
{
  "displayName": "John Smith",
  "mailboxName": "john"
}
Recipients will see John Smith instead of the raw email address. You can update the display name at any time with PATCH /v1/inboxes/:id.

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Multi-tenant routing

Route inbound events by inbox_id. Map each inbox ID to your user/agent/container in your app. Multi-tenant - One account, many inboxes. Create one inbox per agent and route by inbox_id. Multiple inboxes per user - You can create multiple inboxes for the same user. Webhooks include inbox_id so you can identify which inbox received the message.
See Email deliverability for warm-up schedules and content best practices.

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Limits

PlanMax inboxes
Free3
Developer10
Launch200

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Lifecycle

Deleting an inbox (DELETE /v1/inboxes/:id) permanently removes the inbox and all associated messages, threads, and attachments. This is not reversible.