The NoSolicitado Blacklist is an IP-based blocklist specializing in identifying sources of unsolicited email, with a particular focus on Spanish-language spam that other blacklists might miss.
The NoSolicitado Blacklist is a public DNS-based Blackhole List (DNSBL) that focuses on identifying and blocking IP addresses responsible for sending unsolicited emails. It is a type of IP blocklist, meaning it lists the specific IP addresses of mail servers rather than domain names. According to NoSolicitado, it is used by thousands of servers worldwide and processes billions of email queries each month.
This particular blacklist (or blocklist) was created to specifically target unsolicited emails written in Spanish, which may not be detected by other RBLs. It identifies problematic servers by using decoy email addresses, also known as spam traps. When a spammer scrapes these addresses from web pages and sends mail to them, NoSolicitado flags the sending IP address. An IP can be listed if it is associated with a high volume of unsolicited mail. This means you could be listed even if you share a server with another sender who is sending spam.
The blacklist is operated by the organization NoSolicitado.org. They describe themselves as one of the most trusted RBL services in the world, handling over six billion queries monthly. Their stated mission is to combat spam that originates from poorly managed email service providers and unmonitored data centers that fail to prevent such activity.
If you are a server administrator and believe your IP address has been listed erroneously, you can request a review. The organization provides a delisting page on their website to check your IP and dispute the listing.
Before you request removal, you should ensure you have addressed the underlying issue causing the listing. NoSolicitado provides the following guidelines:
Be aware that the organization reserves the right to ignore disputes they consider meritless. Additionally, certain email servers with an extremely poor reputation may not be eligible for removal from this blocklist.
The impact of being on the NoSolicitado blacklist is considered medium. While it may not be as widely used as some of the largest global blocklists, it is very influential within its niche. Since this blacklist is specifically designed to catch Spanish-language spam, being listed can cause significant email delivery problems if you are sending to subscribers in Spanish-speaking countries or regions. Mailbox providers and companies in these areas are more likely to use this RBL to filter their incoming email, meaning your messages could be blocked entirely.
19 resources
How to interpret and assess unknown email blacklists like NoSolicitado?
Should I be concerned about the NoSolicitado blacklist for email sending?
Should I use blacklist or blocklist in email marketing?
What are examples of insignificant or ineffective email blocklists?
What common blocklists or services cause 'message rejected as spam' errors for ESPs?
What is the PSBL (Passive Spam Block List) and how does it work?