# Billing

> Plans, monthly receiving allotment, and metered overage.

Inboundr bills on a simple model: paid plans include a monthly allotment for
**receiving**. Every plan stops at 100% of its allotment; paid plans can lift
that by turning on **pay-as-you-go**, which bills overage in blocks of 1,000
units.

## Plans

| Plan | Received / mo | Domains | Attachments | Price / mo |
| --- | --- | --- | --- | --- |
| **Free** | 200 | 1 | — | $0 |
| **Basic** | 6,000 | 3 | to 10 MB | $4 |
| **Pro** | 50,000 | 50 | to 25 MB | $19 |
| **Scale** | 150,000 | 500 | to 50 MB | $55 |

Two things don't vary by plan and so aren't columns above: **15-day retention**
and **$0.60 per 1,000** of pay-as-you-go overage, both the same on every plan
including Free — which gets the retention but blocks instead of billing.

## How usage is counted

Usage counts in **256 KB units**. Almost all mail is a single unit — a typical
message with no attachments is well under 50 KB — but a large one costs
proportionally more to receive, so it counts for more:

| Message size | Units |
| --- | --- |
| Anything up to 256 KB | 1 |
| 1 MB | 4 |
| 5 MB | 20 |
| 25 MB | 100 |

This is why the **Received** meter on your billing page is a unit count rather
than a message count: if you receive large attachments, that number will be
higher than the number of emails in your inbox, and that difference is real.

<Note>
  The unit only affects **counting**, never delivery: a message is never
  refused or delayed for being large. Attachment *storage* is a separate
  per-plan limit (the table above). Past it the message and its attachment
  details still arrive — the files just aren't kept for download.
</Note>

<Note>
  **Basic** is the entry paid tier: one agent with its own domain and inbox.
  Every paid plan drops Free's daily ceiling — the monthly allotment is yours
  to spend as fast as you need it.
</Note>

Your usage counter resets on your subscription anniversary, not the first of
the calendar month — subscribe on 12 July and the cycle runs 12 Jul → 12 Aug →
12 Sep, which is exactly the window Stripe invoices. Current usage is shown on
the [Billing](https://inboundr.net/console/billing) and
[Settings](https://inboundr.net/console/settings) pages.

Mail [Shield](/concepts/shield) blocks is never delivered, but still counts as
**received**: it had already arrived before any rule could look at it.

## What Free includes

Free is a working inbox, not a preview: 200 received a month on one domain,
with the same 15-day retention as every paid plan. It is the one plan with a
daily ceiling — **50 received per UTC day** — which stops a month's allotment
going in an hour. Past it, mail is refused until midnight UTC.

- Registering a second domain returns `402`.
- Attachment **content** isn't stored. The metadata still arrives — filename,
  type, and size, with `stored: false` — so nothing looks silently missing, but
  [downloading one](/api-reference/attachments/download) returns `402`.

## Message size

Attachment **content** is stored up to your plan's message size — 10 MB on
Basic, 25 MB on Pro, 50 MB on Scale. Larger messages still arrive and are still
stored; only their attachment content is skipped, and the metadata comes through
with `stored: false`.

## Retention

Stored email is deleted **15 days** after it arrives, along with its raw message
and attachments. A daily job does the deleting, so a message may survive a few
hours past the line, never less than the window. Retrieve anything you need to
keep via the [API](/api-reference/emails/list) or route it to a webhook, which
is not subject to retention.

The window is the same on every plan, so changing plans — in either direction —
never changes how long your mail is kept.

## Approaching your allotment

We email you at **80%** and **90%** of your allotment, and again at 100%. Each
notice is sent once per billing period, so a busy month doesn't turn into a
stream of mail.

## Reaching 100%

By default every plan **stops** at its allotment: inbound mail is refused until
the next period, an upgrade, or pay-as-you-go. Refused mail is not stored and
cannot be recovered afterwards.

## Pay-as-you-go

Paid plans can keep going past their allotment by enabling **pay-as-you-go** on
the [Settings](https://inboundr.net/console/settings) page. It is off until you
turn it on: nothing bills above your plan price unless you asked for it.

With it on, overage is charged in **blocks of 1,000 units** at **$0.60 per
block on every paid plan**. A block is charged when you enter it, so one unit
past your allotment costs a full block.

The rate doesn't fall as you move up the plans, because prepaying is what gets
you the cheaper rate: overage always costs more per email than the allotment it
overflows, on every tier. It is there to keep mail moving, not to be a plan.

Turning it off takes effect immediately. If you are already past your
allotment when you do, billing starts blocking straight away.

Free cannot enable pay-as-you-go: it blocks at its allotment, and at its daily
ceiling before that.

## Managing your subscription

Upgrade, downgrade, and manage payment from the
[Billing](https://inboundr.net/console/billing) page. Changes take effect
immediately; your included allotment follows the active plan. Retention and the
overage rate are the same everywhere, so neither changes when you switch.