Does the top level domain (TLD) affect email deliverability?

Key findings

• Reputation correlation: Some TLDs, particularly newer generic TLDs (gTLDs), have been associated with higher rates of spam and abuse, leading to a poorer reputation among mailbox providers. This can affect how your email is perceived, even if your sending practices are legitimate. For more on this, see how top-level domains (TLDs) impact email deliverability.
• Warmup difficulty: Domains with TLDs that have a history of abuse may experience more challenging email warm-up periods, requiring a slower ramp-up of sending volume to build trust.
• Country code TLDs (ccTLDs): Many ccTLDs (like .no or .uk) generally have good reputations because they are often managed by government entities and are less prone to widespread abuse by spammers, unlike some generic TLDs.
• Spamhaus listings: Resources like Spamhaus publish statistics on TLDs with the highest percentages of reported spam, which can be an indicator of potential deliverability challenges. You can check the Spamhaus TLD statistics page for current data.
• Machine learning filters: Modern email filters, especially those using machine learning, may have biases against mail originating from TLDs with a history of spam, even if the individual sending domain has a clean record.

Key considerations

• Prioritize core reputation: While TLDs play a role, your overall domain reputation, email authentication (SPF, DKIM, DMARC), content quality, and recipient engagement are far more critical for deliverability. Focus on these fundamentals first.
• Avoid known problematic TLDs: If considering a new TLD, research its reputation and avoid those frequently appearing on blocklists or known for high spam volumes. This includes many of the newer, less common TLDs. Learn more about less common domain extensions and their impact.
• Relevance and branding: Choose a TLD that is relevant to your brand or geographic target audience. A ccTLD (like .no for Norway) is generally acceptable if your business has a legitimate connection to that region.
• Monitor deliverability: Regardless of your TLD choice, continuously monitor your email deliverability rates and engage with postmaster tools to identify any issues early.

Key opinions

• Perceived risk: Many marketers believe that certain TLDs are inherently riskier than others, primarily due to their association with spam or a lack of widespread trust.
• Legacy TLD preference: There's a strong preference for traditional TLDs like .com, .org, and .net, which are seen as more credible and less likely to trigger spam filters. This is partly due to their long-standing reputation as discussed by Influno regarding cold email domains.
• New gTLD skepticism: Newer generic TLDs (e.g., .xyz, .online, .tech) are often viewed with skepticism, with marketers reporting that they can negatively impact inbox placement or require more strenuous warm-up processes. We have a specific article on how uncommon domain extensions affect email deliverability.
• Industry-specific TLDs: Some marketers try industry-specific TLDs (e.g., .marketing, .agency) but often report mixed results, suggesting they might not offer a significant deliverability advantage and could even pose challenges if abused.

Key considerations

• Brand perception: The chosen TLD also impacts how professional and trustworthy your brand appears to recipients, which indirectly affects engagement and deliverability.
• Cost vs. deliverability: Cheaper or obscure TLDs might seem appealing, but the potential deliverability headaches could outweigh the initial cost savings. For example, consider whether a .info domain affects deliverability compared to a .com.
• Target audience trust: If your audience is accustomed to receiving emails from .com or ccTLDs, an unusual TLD might lead to lower open rates or increased spam complaints, even if your technical setup is perfect.
• Long-term strategy: Marketers often consider the long-term implications, preferring TLDs that are less likely to be blocklisted or become associated with poor sending practices in the future.

Key opinions

• Not a myth: Experts confirm that the idea of TLDs affecting deliverability is not entirely a myth. They acknowledge that some TLDs can make warm-ups more difficult if they are frequently abused. For more on general deliverability issues, see why emails go to spam.
• Registry policies matter: A significant factor is the policies of the TLD registry. If a registry makes it easy and cheap for spammers to acquire domains, the TLD will likely develop a poor reputation affecting legitimate senders.
• ML filter bias: Machine learning filters employed by mailbox providers may exhibit bias against certain TLDs that have a documented history of abuse or poor email practices.
• Dynamic reputation: The reputation of a TLD is not static; it changes regularly based on ongoing activity. What is a blacklist and how does it work is important to understand.
• Country code TLDs are safer: Many country-code TLDs (ccTLDs) are considered safe for email sending because they are often managed by government entities, making them less attractive targets for spammers.
• Avoid .guru, .brain, .xyz: Experts strongly advise against using these and similar new generic TLDs for email sending due to their poor reputations.

Key considerations

• Contextual usage: A ccTLD (like .no) is generally acceptable if your company has a legitimate connection to that country, particularly if you send mail in the local language.
• SpamAssassin impact: While SpamAssassin has old rules related to TLDs, its impact on major mailbox providers is often minimal, primarily affecting smaller, less sophisticated receiving systems.
• Middle-ground TLDs: Some TLDs, like .email, fall into a middle ground, being used by both legitimate senders and spammers. Their deliverability can be similar to .com, dependent on sender practices.
• Focus on fundamentals: While TLD matters, fundamental email best practices such as authentication, content quality, and list hygiene remain paramount for good deliverability.

Key findings

• Domain reputation component: Documentation confirms that the TLD forms part of the broader domain reputation, which is crucial for determining inbox placement. For a full understanding of this, refer to understanding your email domain reputation.
• Filtering mechanism: Mailbox providers' filtering mechanisms may assign reputation scores to TLDs based on aggregate sending behavior observed across all domains under that TLD.
• Abuse patterns: Some TLDs are more frequently used for malicious activities like phishing, spam, or malware distribution, leading to a negative association and increased filtering scrutiny.
• New TLD challenges: Newer TLDs often lack the established positive reputation of older ones, making it harder for legitimate senders to gain trust from the outset. This is especially true for those not immediately identifiable as for-profit businesses. More on this is available in SocketLabs' blog on unofficial TLDs.

Key considerations

• Comprehensive approach: While TLD selection matters, deliverability is a holistic challenge requiring attention to all aspects of email sending, including technical setup and content quality. For a deeper dive, check out boosting email deliverability rates.
• Brand fit: Choose a TLD that aligns with your brand identity and perceived trustworthiness, as this contributes to overall recipient confidence and engagement.
• Monitoring is key: Regularly monitoring deliverability metrics and blocklist status for your chosen TLD is crucial to detect and address any reputation issues promptly.