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
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:
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.
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.
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.
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 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 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 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 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. 
