3rhost launches Portugal's first DNS blacklist against spam
3rhost has created dnsbl.3rhost.pt, a DNS blacklist developed and maintained in Portugal — and, as far as we know, the first of its kind in the country. Our mail servers now automatically reject spam sources before messages ever reach customers' inboxes.
Until now, Portuguese mail servers relied exclusively on foreign blacklists to fight spam. 3rhost decided to change that: we launched dnsbl.3rhost.pt, a DNS blacklist developed, hosted and maintained in Portugal. As far as we know, it is the first national DNS blacklist.
Why this matters
Major international lists are essential, but they look at spam on a global scale. Many campaigns targeting Portugal — written in Portuguese and aimed at Portuguese businesses — go undetected or take too long to be flagged.
Our list is fed by spam that actually reaches our customers' inboxes. This allows us to identify and block new campaigns within minutes, with a clear understanding of the local landscape. It works alongside the international lists we already use — not as a replacement for them.
How it works
Whenever a server attempts to deliver a message to one of our customers, our mail servers query the list. If the sending address is identified as a spam source, the connection is rejected and the message never reaches the inbox.
What changes for you
Nothing that requires any action on your part. Protection is automatic across all our mail servers. In practice, you should notice less spam in your inbox.
If you still receive spam, please forward the message as an attachment to our support team. Every report is reviewed by our team and helps make the list more effective.
No wrongful blocks
Major email providers such as Gmail or Microsoft 365 are never blocked. No address is added to the list without a decision from our team.
Been blocked?
If one of your emails is rejected by our list, you can check the status and request removal at https://dnsbl.3rhost.pt/verificar. Every request is reviewed and a reply is sent by email.
A list open to other Portuguese mail servers
dnsbl.3rhost.pt is available free of charge to other hosting providers and mail server administrators. The more national servers that use it, the more effective the protection against spam targeting Portugal becomes.
The ID Digital team, a web design and digital marketing agency in Aveiro, with over 10 years of experience in digital projects.
