Glossary Entry
What is Mailbox Quota?
Mailbox Quota without the jargon — the definition, the analogy, and why any site owner should care.
The short answer
One email account gets one storage ceiling, its quota, and a full box bounces new mail back to whoever sent it.
What follows: the longer explanation, a picture that holds, the practical stakes, and the places you will genuinely meet it.
By the Hosting & Domains team · Reviewed 18 August 2026
100+
Terms in the jargon buster
2 min
Average read time
Plain
English throughout
24/7
People, if you get stuck
Quotas stop one mailbox stuffed with attachments from eating the whole account's storage. The dangerous part is the failure mode: once it is full, arriving mail is refused, which is a failure you cannot see and an alarming one for whoever sent the message.
The offenders are the same short list every time. Attachments sitting in Sent, a Trash folder untouched since 2019, and years of newsletters. Which turns a clear-out into targeted work instead of an excavation.
A way to picture Mailbox Quota
A letterbox of fixed depth and no more. Pack it full and the postman takes new letters away marked undeliverable, and you find out when a customer rings to ask why their email came back.
Any analogy flattens the detail, naturally — but this one is solid enough to think with, and thinking is what a jargon buster is for.
Why this term earns a page
Watching the quota heads off the worst kind of email failure: the kind nobody notices. An alert at 80 per cent, or simply sizing boxes generously from the start, turns it into a non-event.
That, incidentally, is the bar for any technical term — not 'could I lecture on it' but 'would I recognise it as the answer to my problem'. For this one, you now would.
How it turns up day to day
A sales mailbox fills mid-campaign. Replies bounce for three days before anybody mentions it on the phone. The clear-out takes an hour and the lesson lasts a good deal longer.
Entirely unremarkable once you have seen it — which is the point: most hosting ideas are plain machinery behind an intimidating label.
Where it sits inside your own account
You will meet it in the control panel and now and then in a support thread, usually already set correctly. If this one landed, the natural follow-ups are IMAP, Disk Space, Webmail and Inode.
Support means a person at any hour, and the remit covers the awkward practical questions other hosts hand straight back.
A jargon buster from the people who answer the tickets
Sooner or later every confusing hosting term turns into a support ticket, so we defined the hundred commonest ones properly — once, in the same plain English we use with customers.
Support means a person at any hour, and the remit covers the awkward practical questions other hosts hand straight back.
- 100+ entries, plain English all the way
- Ordinary analogies, working examples
- Neighbouring ideas linked together
- Written by our own support engineers
Why Hosting & Domains
Standard on every plan
Stakes made explicit
More than what a thing is: the moments it turns out to be the answer to a problem you have.
Cross-wired entries
Related terms point at each other, so one lookup compounds into working knowledge.
Tied to real hosting
Examples name platforms you would genuinely use, never an abstract diagram on a whiteboard.
The next step, drawn out
Carry on into IMAP and Disk Space — ideas rarely travel alone, so the neighbours are linked in.
Analogies that hold
Every concept comes with a mental model that returns exactly when you need it.
This term, properly landed
Mailbox Quota defined, pictured by analogy and located in your own panel — recognise-level after a single read.
Quick Start
Order placed to site online
- 1
Find it in your own account
Open the control panel and find where this idea sits — a definition turns into understanding the moment it attaches to your own site.
- 2
Check the defaults as they stand
Look at how your account has it configured. Nine times in ten the default is right, and a check turns the guess into certainty.
- 3
Chase the neighbouring terms
Hosting terms travel in groups — IMAP, Disk Space and Webmail finish this one's picture, each a two-minute read away.
Built In
Fitted to every plan
- Staging copies for trying a change before it goes live
- People on the support desk every hour of every day
- PHP versions set per site from the control panel
- The name's first year included when you order annually
- Mailboxes that answer at the name you hold
- A daily copy, with restores you run yourself from the panel
- Upgrades applied in place, with no migration when you change plan
- No set-up charge at any point, and no joining fee
- Money back within 30 days on hosting plans, 7 on reseller
- Your existing site brought across by our engineers, at no charge
Frequently Asked
The questions that come up most
How large should each mailbox be?
Be generous. Attachments build up far faster than anybody predicts, and storage costs a great deal less than a bounced enquiry. Give the busy boxes gigabytes rather than megabytes, and look at them again in a year.
How do I spot a mailbox running out of space?
Your panel shows usage per box, webmail often warns as you approach the ceiling, and some setups will email you at a threshold. Failing all that, a quarterly glance at usage costs nothing and rules the silent-bounce scenario out entirely.
How quickly can a site be live?
Quickly — minutes rather than days. The account opens the moment payment clears, the domain (free for the first year on annual plans) attaches straight away, and the one-click installer has WordPress or any of 240+ applications running before your coffee cools. Site already somewhere else? Send the details and we move it free, normally within a day.
What happens when I outgrow the plan?
You upgrade in place. Plan changes are made from the client area with no migration and no downtime, and the range runs from small shared accounts through VPS to full dedicated machines. Growth becomes a setting on the account rather than a search for a new host.
Keep reading
Inode
Each file or folder gets one index entry in the filesystem, called an inode, and since hosting plans cap th…
Disk Space
Disk space is the ceiling on everything your hosting account holds, with site files, databases and email al…
How to Free Up Mailbox Storage
Step by step, with every snag flagged before you get to it.
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