IONOS Mailbox nearly full

What to do when your IONOS mailbox is nearly full or full.

If your IONOS Mailbox filles up, you may not receive any more email until you clear space.


Please note, if you receive an IONOS Mailbox full or near full – the message refers to the IONOS mailbox limit on the internet – not the one on your computer.

There are 3 sizes of mailbox:-

• Mail Basic – 2GB. The fee for this is usually included on the domain registration or other services.
• 10 GB only available to a small number of clients and is not generally available.
• Mail Business – 50 GB. There is a standing fee of £7 per month for this payable by Direct Debit. This is useful for clients who only need a small number of large inboxes and have other mailboxes which do not need to be any larger than 2GB. Otherwise, we recommend using Microsoft 365 instead.

The techniques for dealing with a full mailbox is different for POP and IMAP accounts, so we will deal with how to clear space in them separately.

If you have a POP account, this is what to do.

A POP mailbox is stored in 2 places, 1 is on the IONOS mailbox on the internet and the other is on your computer.

The mailbox on your computer should be able to go to 50GB although we would strongly recommend archiving as much of it as possible as your computer (Outlook) may become unstable with the very large mailbox.

First, run Outlook on your computer to make sure the Outlook mailbox is up to date. If you want, you can export the mailbox so you have a backup of it. File, Open & Export, Import/Export, Export to a file, Outlook Data File (.pst), Next, select the full mailbox, Next and select a location to store the .pst file.

Then, log onto your IONOS webmail here.

Since you are using a POP mailbox you should delete email from the IONOS webmail mailbox directly. Start by Clearing the spam then emptying the trash. The changes won’t take place immediately so keep refreshing the page to see how much space you are creating.

Then clear out the older email which should remain on your computer/ Outlook. You can judge how much you need to delete and keep checking how much space you have cleared.

If you are using an IMAP mail service.

You don’t need to log onto your webmail to clear space in your IONOS mailbox. This is because Outlook synchronises the mail data on your computer with the IONOS mailbox. So whatever happens on one mailbox, happens the other.

Start by clearing the Spam and Trash folders (if you have them) and then emptying the deleted items folder.

Once that’s done, you should move existing emails to a separate datafile on your computer The most popular name for this additional datafile is archive, although you might want to call it ‘sent items up to end of 2024’. The later format is handey as you can use it to organise multiple data files.

By all means, log onto your webmail to confirm how much space you have cleared.