How concerned should I be about SPFBL DNSBL for email deliverability to Brazil?
Matthew Whittaker
Co-founder & CTO, Suped
Published 3 Jun 2025
Updated 19 Aug 2025
6 min read
When managing email deliverability, especially for regions like Brazil, it's natural to encounter various DNS-based blacklists (DNSBLs) that can impact your sending. One such blocklist (or blacklist) that often comes up in discussions is SPFBL.net. The question of how much concern it warrants for email deliverability, particularly in Brazil, is a valid one.
Many email senders, myself included, have pondered the actual impact of SPFBL. While some blocklists are universally recognized and can severely hinder your email campaigns, others might have a more localized or niche influence. Understanding this distinction is crucial for prioritizing your deliverability efforts and focusing on what truly matters.
The email landscape is complex, with numerous factors influencing whether your messages reach the inbox or land in spam. DNSBLs are just one piece of this puzzle, and their relevance can vary significantly depending on your target audience and the specific mailbox providers they use. Let’s dive into SPFBL.net and its practical implications for sending emails to Brazil.
SPFBL.net operates as a DNSBL primarily based in Brazil. This means it can indeed have some influence on email deliverability within that country. Unlike global giants that dictate deliverability for major mailbox providers worldwide, SPFBL.net's impact is generally more concentrated on local Brazilian ISPs and mail servers that choose to utilize its data.
From what I've observed, the overall volume of bounces directly attributable to SPFBL.net is relatively low compared to the total number of email bounces you might experience. While I have seen SPFBL-specific rejections, the frequency is not as high as with some other more pervasive blocklists. This suggests that while it exists and can cause issues, it may not be a primary driver of deliverability problems for most senders.
It's important to remember that most blocklists today do not singularly govern email deliverability or inbox placement. Mailbox providers use a combination of factors, including sender reputation, content analysis, engagement metrics, and various authentication protocols like SPF, DKIM, and DMARC. Therefore, being listed on a blocklist like SPFBL.net is often one of many signals, not the sole determinant of your email's fate.
Typical deliverability impact
Scope: Primarily affects Brazilian email recipients using ISPs or mail servers that actively query SPFBL.net.
Volume: Generally responsible for a small percentage of overall bounces, especially compared to more widely used global blocklists. You can read more about email blocklists in our comprehensive guide.
Severity: Can result in temporary deferrals (greylisting) or hard bounces, preventing delivery to affected inboxes.
Bounce codes and their meanings
While the overall impact might be limited, it's still prudent to understand the common bounce codes you might encounter if your IP or domain is listed on SPFBL.net. These codes can give you insight into the specific reason for the rejection, whether it's a permanent block or a temporary deferral.
Some common bounce messages indicate a direct SPFBL block, often referencing dnsbl.spfbl.net in the error message. It's crucial to differentiate between hard bounces (permanent rejections) and soft bounces (temporary issues that might resolve with retries). Knowing the difference helps in managing your email list and preventing unnecessary recipient removal.
Common SPFBL bounce messages
smtp;550 5.7.1 SPFBL you are permanently blocked on this server. See <http://spfbl.net/en/feedback>
smtp;451 4.7.1 SPFBL greylisted message. See <http://spfbl.net/en/feedback>
smtp;554 5.7.1 Service unavailable; Client host [ip.address] blocked using <http://dnsbl.spfbl.net>; <https://matrix.spfbl.net/ip.address>
smtp;550 Email blocked by <http://dnsbl.spfbl.net>
If you receive a hard bounce, it indicates a permanent rejection, and continued attempts to send to that address will likely result in further deliverability issues. Transient errors, on the other hand, suggest a temporary problem that your mail server should ideally retry later. Monitoring these bounce codes is a key part of maintaining good email deliverability.
SPFBL.net vs. major blacklists
While SPFBL.net might have some local relevance, it's generally considered less influential than many other widely adopted blocklists. For instance, blocklists like Spamhaus or Proofpoint (formerly Cloudmark) have a far broader reach and are integrated into the filtering systems of major mailbox providers globally.
The key distinction lies in adoption. Major email providers like Google and Microsoft do not rely heavily, if at all, on SPFBL.net for their primary spam filtering decisions. Their systems are far more sophisticated, using artificial intelligence and a vast array of reputation signals to determine inbox placement. This means that a listing on SPFBL.net is unlikely to be the sole reason for your emails landing in the spam folder at a major mailbox provider.
SPFBL.net
Reach: Primarily focused on the Brazilian email ecosystem. Some smaller local providers may use it.
Delisting: Historically, the delisting process has been a point of contention, with some users reporting difficulties or requirements for payments. More information is available on their delist page.
Impact: Can cause minor deliverability hiccups for Brazilian recipients but often not a critical block.
Major global blacklists
Reach: Widely adopted by major internet service providers (ISPs) and mailbox providers globally.
Delisting: Typically free, but requires addressing the root cause of the listing. Learn more about checking blocklists.
Given its more localized nature, SPFBL.net doesn't typically warrant the same level of urgent concern as, say, a Spamhaus SBL listing. However, for senders whose primary audience is in Brazil, it's certainly worth being aware of and addressing if you notice a consistent pattern of bounces attributed to it. For more context, you can read about new blocklists and their typical impact.
Remediation and best practices
Even if SPFBL.net isn't a top-tier blocklist, it's still best practice to avoid being listed. Most listings occur due to sending unsolicited email or poor list hygiene. If you find your IP or domain listed, the first step is to identify the root cause of the listing. This often involves reviewing your sending practices, list acquisition methods, and checking for any compromised accounts or systems.
SPFBL.net, like many other blocklists, aims to reduce spam by identifying and blocking sources of unwanted email. They often provide a feedback system and a delisting process. While there have been reports of unusual delisting requirements, such as those related to WHOIS information or payment, it's essential to follow their stated procedures if you wish to remove your listing.
Steps to take for SPFBL delisting
Identify cause: Pinpoint why your IP or domain was listed. This could be due to spam complaints, high bounce rates, or potentially even private WHOIS information.
Review practices: Ensure your email sending practices comply with anti-spam regulations, especially those relevant to Brazil.
Follow delisting process: Visit the SPFBL delisting page and follow their instructions carefully.
For ongoing protection, implement and enforce strong email authentication. This includes SPF, DKIM, and DMARC. These protocols help mailbox providers verify that your emails are legitimate and prevent spoofing, which can inadvertently lead to blocklist listings.
Views from the trenches
Best practices
Maintain meticulous email list hygiene by regularly removing inactive or bouncing addresses.
Implement double opt-in for all new subscribers to ensure explicit consent for receiving emails.
Routinely monitor bounce rates and spam complaint rates to identify and address issues promptly.
Ensure SPF, DKIM, and DMARC records are correctly configured and aligned for your sending domains.
Common pitfalls
Ignoring SPFBL.net listings entirely, particularly if a significant portion of your audience is in Brazil.
Failing to identify the root cause of a listing, leading to recurring issues even after delisting.
Relying solely on external blocklist monitoring without analyzing your own bounce logs for specific rejection reasons.
Not maintaining proper email authentication, which can negatively impact overall sender reputation.
Expert tips
Monitor SPFBL.net more closely if your email campaigns consistently target Brazilian audiences.
Focus on overall email hygiene and authentication, as these universally improve deliverability.
Analyze bounce codes carefully to distinguish between temporary greylisting and permanent blocks.
Consider SPFBL.net as one data point among many, rather than a critical threat to global deliverability.
Marketer view
Marketer from Email Geeks says they rarely see bounces specifically attributed to SPFBL, so its impact is generally low.
2019-12-19 - Email Geeks
Marketer view
Marketer from Email Geeks says that while they do see a couple of SPFBL bounces, the number is insignificant compared to their total bounce volume, mostly affecting Russian and Brazilian regions.
2019-12-19 - Email Geeks
The bottom line
Overall, while a listing on SPFBL.net (or any blocklist, for that matter) is never ideal, it shouldn't be a source of extreme alarm for most email senders, even those targeting Brazil. Its influence is more regional and typically not as impactful as major global blocklists. Your focus should always be on maintaining excellent sending hygiene and proper email authentication.
By following email deliverability best practices, like sending relevant content, managing subscriber consent, and ensuring your authentication records are correctly set up, you'll naturally mitigate the risks associated with most blocklists, including SPFBL.net. Consistent monitoring of your email deliverability metrics and swift action on any significant issues will always be your strongest defense.
Google and 
Microsoft do not rely heavily, if at all, on SPFBL.net for their primary spam filtering decisions. Their systems are far more sophisticated, using artificial intelligence and a vast array of reputation signals to determine inbox placement. This means that a listing on SPFBL.net is unlikely to be the sole reason for your emails landing in the spam folder at a major mailbox provider.
