# Mailboxes

A mailbox is a real email address that can send and receive messages.

## Addressing

Every mailbox has a **full address** formed from the local part and domain:

- **Platform email:** `slug@robotomail.co` — available on all plans. The slug is your account identifier, chosen at signup.
- **Custom domain:** `address@yourdomain.com` — requires a verified domain on the paid plan. See [Domains](https://robotomail.com/docs/concepts/domains).


## Status lifecycle

A mailbox can be in one of three states:

- **ACTIVE** — Can send and receive email. Default state on creation.
- **PAUSED** — Cannot send or receive email. Inbound email for paused mailboxes is not polled. You can pause a mailbox via `PATCH /v1/mailboxes/:id`.
- **PAUSED by billing** — When a paid account downgrades, extra mailboxes are paused automatically with a `pausedByBilling` flag. They are reactivated on upgrade.


## Plan limits

Free accounts include **3 mailboxes** with **100 sends per day** and **5,000 sends per month** per mailbox. Paid plans start at **$19/month** with 10 mailboxes and 500 sends per day — Growth and Scale plans include unlimited monthly sending. The daily send counter resets at midnight UTC, and the monthly counter resets at midnight UTC on the first of each month.

See [Limits & Quotas](https://robotomail.com/docs/concepts/limits) for full plan details.


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