Spam filter
One spam filter for the whole organisation, running on our servers with no outside service. Light, Standard or Strict, with Blocked and Trusted senders you can edit.

What it does
Caught on arrival
Judged when it arrives
It weighs the sender checks (SPF, DKIM, DMARC), your provider’s spam flag, and display names that mimic another address.
You choose how strict
Light lets more through. Standard is the default. Strict catches more, and sometimes real mail too.
Your team teaches it
Three different people reporting a sender within 30 days sends that sender’s mail to Spam for everyone.
Trusted senders
A trusted sender is never marked as spam, on mail that proves it came from them. Domains you write to count.
How it works
Report, block, trust
- 1
Mail arrives
The filter checks it. Suspected spam goes to Spam instead of the Inbox, with a banner that says why it is there.
- 2
You correct it
Mark as spam teaches the filter. In Spam, choose Not spam to put a message back. Pictures and links stay off in Spam.
- 3
You tune it
In Settings › Spam & senders, set how strict the filter is, how long Spam is kept, and who is Blocked or Trusted.
Good to know
The details
- Who can use it
- Everyone can mark spam, and block or trust senders for themselves. Administrators set the strictness and block senders for everyone.
- Where
- Settings › Spam & senders, with tabs for Blocked, Trusted and Images.
- Spam is emptied
- After 7, 30 or 90 days, as an administrator chooses. The default is 30.
- Your provider
- Marking spam changes DMU Mail only, not your provider’s server. Mail your provider already put in its junk folder arrives in Spam.
Be one of the first teams in
We let a few organisations into the private beta every week. Join the waitlist and we’ll email you when there’s room for your team.
Three quick questions. No card needed.