What impact does being listed on UCEPROTECT have on email deliverability?

Summary

The impact of a UCEPROTECT listing on email deliverability is complex and debated. A Level 1 listing indicates direct spam activity from your IP, while Levels 2 and 3 suggest a compromised network. While some sources emphasize that being listed on blocklists like UCEPROTECT can severely affect deliverability by leading to email rejections or spam folder placement and damage sender reputation, many experts and email marketers report that its influence is limited as major ISPs and corporations are moving away from using UCEPROTECT. Some even advise ignoring it. The relevance of UCEPROTECT varies depending on the recipient's email provider and spam filtering setup. Key to mitigating any potential negative effects includes implementing proper email authentication (SPF, DKIM, DMARC), maintaining clean email lists, actively monitoring IP and domain reputation, and using deliverability testing tools. Even major ESPs such as AWS, SendGrid, Mailchimp and Sparkpost have been listed on UCEPROTECT in the past, indicating that UCEPROTECT may cast a wide net that could include legitimate senders.

Key findings

  • Variable Impact: UCEPROTECT's impact is inconsistent, ranging from significant deliverability issues to negligible effects, based on different accounts.
  • Level Significance: The listing level (1, 2, or 3) corresponds to different problems: direct spamming (Level 1) vs. compromised network (Levels 2/3).
  • Limited Adoption: Many major ISPs and corporations are no longer relying on UCEPROTECT data, diminishing its overall relevance.
  • Regional Differences: UCEPROTECT sees more usage in specific regions, like Germany, but primarily among smaller domains.
  • Authentication Mitigates: Proper email authentication (SPF, DKIM, DMARC) can help mitigate the impact of blocklist listings in general.

Key considerations

  • Monitor Reputation: Actively monitor IP and domain reputation for blocklist listings to proactively address any deliverability concerns.
  • Use Testing Tools: Utilize deliverability testing tools to assess whether emails are being blocked and pinpoint any underlying issues.
  • Implement Best Practices: Prioritize implementing and maintaining email sending best practices, like clean lists and engaging content, over solely focusing on UCEPROTECT.
  • Contextualize Listing: Understand the specific reasons for a UCEPROTECT listing before taking action, as its impact might be minimal depending on the recipient's setup.
  • Consider Alternatives: If concerned about deliverability, focus on best practices and monitor other, more widely used blocklists, rather than solely concentrating on UCEPROTECT.

What email marketers say
12Marketer opinions

Being listed on UCEPROTECT can have varying impacts on email deliverability. While some sources suggest it can severely affect deliverability by causing emails to be rejected or sent to spam, others indicate that its influence is limited because many major ISPs and email providers don't heavily rely on this blocklist. The level of impact also depends on whether the listing is Level 1 (IP address sending spam) or Level 2/3 (bad neighbors). Best practices for email sending, such as clean lists and proper authentication, can minimize negative consequences. Monitoring IP and domain reputation and using deliverability testing tools are crucial for identifying and addressing potential issues. Ultimately, the relevance of a UCEPROTECT listing is not universally consistent and depends on the recipient's email provider and spam filtering setup.

Key opinions

  • Variable Impact: UCEPROTECT's impact on deliverability ranges from severe to limited, depending on the specific circumstances.
  • Level Matters: The UCEPROTECT listing level (1, 2, or 3) signifies different issues, impacting the severity of the problem.
  • Not Universally Used: Many major ISPs and email providers do not heavily rely on the UCEPROTECT blocklist.
  • Authentication Helps: Proper email authentication and clean sending practices can minimize the negative consequences of being listed.

Key considerations

  • Monitor Reputation: Actively monitor your IP and domain reputation to detect and address potential blocklist listings promptly.
  • Testing Tools: Use deliverability testing tools to check if your emails are being blocked and identify underlying issues.
  • Implement Best Practices: Adopt and maintain email sending best practices, including list hygiene, authentication (SPF, DKIM, DMARC), and engaging content.
  • Understand Reasons: Understand the specific reasons for being listed on UCEPROTECT to take appropriate corrective actions.
Marketer view

Email marketer from Mailjet shares that blocklists can severely impact email deliverability, leading to emails being rejected or sent to the spam folder. Being listed on a major blocklist can damage sender reputation.

December 2021 - Mailjet
Marketer view

Email marketer from HubSpot answers that while a listing on UCEPROTECT could have some negative consequences for a sender, a good way of minimizing impact is to adopt best practices for email sending (e.g. keep lists clean, authenticate emails, send engaging content).

February 2022 - HubSpot
Marketer view

Email marketer from SenderGuardian explains the process of getting removed from blocklists, which may involve contacting the blocklist provider and demonstrating improved sending practices.

September 2024 - SenderGuardian
Marketer view

Email marketer from Reddit shares that while a UCEPROTECT listing can cause some deliverability issues, many major ISPs and email providers do not heavily rely on this blocklist, so the impact may be limited.

June 2023 - Reddit
Marketer view

Email marketer from Litmus recommends using deliverability testing tools to check if your emails are being blocked by certain lists and to identify potential issues with your email setup.

November 2021 - Litmus
Marketer view

Email marketer from EmailToolTester explains that spam filters use blocklists as one factor in determining whether an email is considered spam, meaning that a listing can significantly impact deliverability rates.

May 2024 - EmailToolTester
Marketer view

Email marketer from Talos Intelligence highlights the importance of actively monitoring your IP and domain reputation to identify and address any potential blocklist listings promptly.

April 2021 - Talos Intelligence
Marketer view

Marketer from Email Geeks explains that Level 1 means it's something going on from your IP and they tell you what exactly on their website, Level 2 and 3 means you have "bad neighbors".

September 2021 - Email Geeks
Marketer view

Marketer from Email Geeks shares their experience of sending email from an AWS data center, resulting in all IPs being listed on UCE Protect 3 (and sometimes 2), but they haven't noticed any impact from it.

February 2023 - Email Geeks
Marketer view

Marketer from Email Geeks shares that UCEprotect is not widely used and suggests ignoring it.

October 2023 - Email Geeks
Marketer view

Email marketer from Spamhaus highlights the difference between various blocklists and their impact on deliverability, emphasizing the importance of understanding the specific reasons for being listed.

September 2024 - Spamhaus
Marketer view

Email marketer from StackOverflow comments that UCEPROTECT listings are not universally considered a major indicator of spam and their impact varies depending on the recipient's email provider and spam filtering setup.

November 2022 - StackOverflow

What the experts say
5Expert opinions

The impact of a UCEPROTECT listing on email deliverability is debated among experts. While it's used more in certain regions, particularly Germany, its overall effectiveness and adoption are questionable. Major email providers and corporations have largely moved away from using UCEPROTECT data. Some experts suggest that if you're focused on serious deliverability, UCEPROTECT may not warrant significant attention, while others emphasize the importance of actively monitoring your IP address for any signs of listing as a general practice for maintaining high deliverability.

Key opinions

  • Regional Usage: UCEPROTECT sees more use in specific countries, such as Germany, but even there, it's primarily among smaller domains.
  • Limited Relevance: Major email providers and corporations are increasingly ignoring UCEPROTECT data.
  • Not a Primary Concern: Some experts believe focusing on UCEPROTECT is unnecessary for serious deliverability efforts.
  • Major ESPs Affected: Even major ESPs like AWS, Sendgrid, Mailchimp, and Sparkpost have been listed on UCEPROTECT at levels 2 and 3 in the past.

Key considerations

  • Monitor IP: Regardless of UCEPROTECT's impact, actively monitor your IP address for listing signs as a general best practice.
  • Focus on Fundamentals: Prioritize core deliverability practices, such as email authentication (SPF, DKIM, DMARC) and list hygiene, over fixating on UCEPROTECT.
Expert view

Expert from Email Geeks states that no one who cares about email deliverability pays attention to UCEPROTECT.

May 2022 - Email Geeks
Expert view

Expert from Spam Resource shares that knowing what your IP address is doing, and actively looking for signs of listing is important in having high deliverability

July 2022 - Spam Resource
Expert view

Expert from Word to the Wise explains that while UCEPROTECT is a blocklist, its effectiveness and adoption vary, and being listed doesn't automatically mean emails will be blocked everywhere; many major ISPs and corporations have stopped using their data.

June 2023 - Word to the Wise
Expert view

Expert from Email Geeks mentions that UCEProtect is used a little more widely in some countries (like Germany) but a lot of the folks using it are small domains with very few users.

June 2023 - Email Geeks
Expert view

Expert from Email Geeks mentions that AWS, Sendgrid, Mailchimp, and Sparkpost have been listed at levels 2 and 3 in the past.

December 2021 - Email Geeks

What the documentation says
4Technical articles

According to documentation, a UCEPROTECT listing indicates spam activity or a compromised network. Microsoft uses blocklists to filter spam and protect users, potentially blocking emails from listed sources. Proper email authentication (SPF, DKIM, DMARC) is critical for improving deliverability and mitigating the impact of blocklists. Google considers blocklists as one factor in assessing sending reputation, which can lead to emails being marked as spam or blocked.

Key findings

  • Listing Indicates Issue: A UCEPROTECT listing suggests either direct spam activity from an IP (Level 1) or a compromised network hosting multiple spammers (Levels 2/3).
  • Microsoft Uses Blocklists: Microsoft actively uses blocklists, potentially preventing emails from listed IPs from reaching Outlook.com and Hotmail inboxes.
  • Authentication is Key: Proper email authentication (SPF, DKIM, DMARC) is crucial for improving deliverability and mitigating the effects of blocklists.
  • Google Considers Blocklists: Google factors in blocklist information when assessing sending reputation, which impacts whether emails are marked as spam or blocked.

Key considerations

  • Address Spam Activity: If listed on UCEPROTECT, investigate and eliminate any spam activity originating from your IP or network.
  • Implement Authentication: Ensure proper email authentication (SPF, DKIM, DMARC) is in place to improve deliverability and build trust with email providers.
  • Maintain Good Reputation: Prioritize maintaining a good sending reputation with email providers like Google by adhering to best practices and avoiding spam triggers.
  • Monitor Blocklists: Actively monitor your IP address and domain for listings on various blocklists to proactively address any potential deliverability issues.
Technical article

Documentation from RFC Editor specifies that proper email authentication (SPF, DKIM, DMARC) is crucial for improving email deliverability and can help to mitigate the impact of blocklist listings.

November 2024 - RFC Editor
Technical article

Documentation from Google Postmaster Tools explains that Google considers multiple factors, including blocklists, when assessing the sending reputation of an IP address or domain. A poor sending reputation can lead to emails being marked as spam or blocked.

July 2022 - Google
Technical article

Documentation from UCEPROTECT FAQ explains that a listing in UCEPROTECT-Level1 indicates that the listed IP address has sent spam. Listing in Level 2 or 3 indicates a compromised network, due to too many spammers using the network.

August 2024 - UCEPROTECT
Technical article

Documentation from Microsoft explains that being on a block list can prevent your emails from reaching Outlook.com or Hotmail inboxes. Microsoft uses various block lists to filter spam and protect users.

May 2022 - Microsoft