How do TLDs get a reputation for being 'abused'?

Mailbox providers and security organizations monitor TLDs for patterns of spam and malicious activity. They assess factors like the percentage of bad domains within a TLD, the volume of spam originating from it, and the responsiveness of its registry to abuse complaints. This data influences how strictly emails from a given TLD are filtered.

Which specific TLDs are commonly listed as most abused?

While .com has the largest raw number of malicious domains due to its size, TLDs often cited for high abuse *percentages* include .TK, .ML, .GA, .CF, .GQ (due to free registration), and newer gTLDs like .XYZ, .TOP, and .BUZZ.

Can the TLD of my sending domain affect my email deliverability?

Yes, it can. Emails from TLDs with a poor reputation or a high percentage of spam are more likely to be sent to the spam folder, delayed, or outright rejected, even if the individual sender has good practices. This is often referred to as 'guilt by association' and affects email deliverability .

What if my current domain uses an abused TLD?

If you're already using a domain with a TLD that has a questionable reputation, focus on impeccable sending practices: acquire contacts legitimately, send relevant content, maintain list hygiene, and ensure all your email authentication records (SPF, DKIM, DMARC) are correctly configured. Consistent good behavior can slowly improve your individual domain's standing.

What TLD is recommended for general email sending?

While .com is most commonly used, and therefore hosts the most spam by volume, it still offers the best deliverability due to its overall trust and widespread acceptance. For specific niches, other reputable gTLDs like .org or .net are strong choices. If you need a regional presence, a reputable ccTLD can also work well.

What is the most abused TLD (Top-Level Domain) for spam? - Sender reputation - Email deliverability - Knowledge base

When we talk about email deliverability, the domain name you use plays a significant role in whether your messages land in the inbox or the spam folder. One aspect that often raises questions is the top-level domain, or TLD. This is the last segment of your domain name, like .com, .org, or .net.

It is not uncommon for people to wonder if certain TLDs are inherently more prone to spam, and indeed, some are far more abused than others. The perception of a TLD can heavily influence how mailbox providers and their filters treat emails originating from it.

Different organizations compile lists of abused TLDs based on various criteria, such as the percentage of malicious domains within a TLD or the raw number of spam domains. This means that while one TLD might have a high percentage of bad domains, another might host a larger absolute number of them due to its sheer size.

Understanding which TLDs are most frequently exploited by spammers and cybercriminals is crucial for protecting your own email sending reputation. It helps you make informed decisions when choosing your domain name and managing your email campaigns.

Understanding the most abused TLDs

When we delve into which TLDs are most abused for spam, there isn't always a single, definitive answer. The Spamhaus project, a leading authority in fighting spam, regularly publishes data on this. Their reports often highlight a mix of country code top-level domains (ccTLDs) and generic top-level domains (gTLDs).

For instance, historically, certain ccTLDs such as .TK (Tokelau), .ML (Mali), .GA (Gabon), .CF (Central African Republic), and .GQ (Equatorial Guinea) have appeared on abused TLD lists due to their free or very cheap registration policies. These policies make them attractive to spammers who can easily acquire and discard domains.

Among the gTLDs, new extensions like .xyz, .top, .buzz, .loan, and .men have often shown higher rates of abuse. These domains are sometimes chosen by spammers because they are newer, potentially less monitored, and can be acquired at very low costs, enabling bad actors to quickly register many domains for their illicit activities.

High-risk TLDs

Free or cheap registration: TLDs like .TK, .ML, .GA, .CF, .GQ, .XYZ, and .TOP are often attractive to spammers due to low or no registration fees, facilitating bulk acquisition for disposable domains. This contributes to them having a disproportionately high rate of malicious activity, as detailed in reports from cybercrime information centers.
Lack of strong abuse policies: Some registries and registrars have lax enforcement against abuse, making these TLDs a haven for spammers and phishers. This is a critical factor influencing their reputation. This means there may be less filtering of these newer and sometimes less common domain extensions.

The .com versus niche TLDs debate

Despite the high percentage of abuse in certain new gTLDs and ccTLDs, it's worth noting that TLDs like .com, due to their sheer volume of registrations, often host the largest raw number of malicious domains. While the percentage of abusive domains within .com might be small, the total count can still be substantial because it is such a widely used TLD. This means if you are on a blacklist or a blocklist from a .com domain, it is likely due to your own sending practices.

The key takeaway is that mailbox providers, alongside organizations like PhishLabs, monitor and track abuse across all TLDs. Their algorithms consider not just the absolute numbers but also the reputation of the TLD and its associated registrars. This means that a TLD with a consistently high percentage of malicious activity will likely face stricter filtering, potentially impacting all senders using that TLD, even legitimate ones.

This is why choosing a reputable TLD is part of a strong deliverability strategy. It helps you avoid your emails going to spam due to factors beyond your direct control, such as the overall reputation of the TLD you're operating under.

The dilemma of .US domains

Interestingly, even a ccTLD like .US, intended for use by United States entities, has shown up on lists of heavily abused domains. Reports suggest that the .US domain can be a target for spammers. While it may seem counterintuitive for a country's official TLD to be abused, it often comes down to how lenient or strict the registration and abuse enforcement policies are.

Registration requirements: Despite seemingly stricter requirements for .US, loopholes or inconsistent enforcement can still allow bad actors to register domains for spamming purposes.
Perceived legitimacy: Spammers might target .US domains because they believe it lends an air of legitimacy to their messages, potentially increasing the chance of recipients opening them.

Choosing a domain for deliverability

When choosing a domain for your email sending, especially for marketing or cold outreach, it's wise to consider not just the availability and cost, but also the deliverability implications of the TLD. While specific TLDs can pose higher risks, the core of your email deliverability still rests on your sending practices and sender reputation.

Reputable TLDs: Sticking to well-established TLDs like .com, .org, or .net generally provides a more stable foundation for your sending reputation. If you're a US-based entity, using a .US domain might seem appropriate, but be mindful of its history in spam reports. Consider if you should block .US TLD for email signups based on your audience.
New gTLDs and cold email:Newer TLDs might face skepticism from mailbox providers. If you're engaged in cold email, this could add an unnecessary hurdle to your efforts.

Impact on email deliverability and blocklists

The impact of a TLD on deliverability is directly tied to the reputation it carries. Mailbox providers maintain internal blocklists (or blacklists) and often consult external ones like DNSBLs (DNS-based blocklists) to filter incoming email. If a TLD is known for high abuse rates, it's more likely that emails from domains within that TLD will be scrutinized or even outright rejected. This is why it's so important to understand what a blocklist is.

For legitimate senders, being associated with a heavily abused TLD can be an uphill battle. Even if your sending practices are impeccable, you might still suffer from the guilt by association. This is particularly true for smaller senders or those just starting to build their sending reputation, as they have less historical data to counteract a TLD's poor standing. We have a separate guide that explores the difference between a blacklist and a blocklist.

Choosing a TLD with a cleaner reputation is one of many factors that contribute to a positive sending journey. It removes one potential hurdle in ensuring your emails consistently reach the inbox.

Protecting your sender reputation

For marketers and businesses, safeguarding your sender reputation is paramount. While the TLD is a factor, it is by no means the only one. Your entire email infrastructure and sending practices contribute to your deliverability. This includes maintaining clean email lists, sending relevant content, and authenticating your emails properly with SPF, DKIM, and DMARC.

Regularly checking your domain's reputation and monitoring for any blocklist (blacklist) appearances is critical. Tools and services exist specifically for this purpose, providing insights into how your domains and IPs are perceived by mailbox providers. This proactive approach allows you to address issues before they significantly impact your campaigns.

Ultimately, the choice of TLD is an important strategic decision that can influence your email deliverability. Opting for TLDs with a strong, clean reputation is generally the safest bet to avoid unnecessary hurdles and ensure your messages reach their intended recipients. However, always remember that your sending practices will always be the most important factor in maintaining a good domain reputation.

Best practices for senders

Choose wisely: Select TLDs known for good reputation, such as .com, .org, or country-specific ones with robust abuse policies. Consult lists of TLDs to avoid if unsure.
Monitor reputation: Regularly check your domain's health with tools like Google Postmaster Tools and other reputation services.
Implement authentication: Ensure your SPF, DKIM, and DMARC records are correctly configured. This is a fundamental step for email security.
Quality over quantity: Focus on sending to engaged recipients and providing valuable content to build a strong sender reputation, regardless of your TLD choice.

Recognizing patterns in TLD abuse

TLD	Common Use	General Reputation
.com	Commercial websites, general use.	High volume, generally good. Hosts many malicious domains by raw count, but low percentage.
.org	Non-profit organizations.	Generally good, trusted.
.net	Networking, general use.	Generally good, but can be targeted by spammers.
.tk, .ml, .ga, .cf, .gq	Country codes, often free registration.	Very high abuse rates due to free/cheap nature. Frequently blocklisted (blacklisted).
.xyz, .top, .buzz	Generic use, newer gTLDs.	Often high abuse rates. Can be perceived as suspicious by filters. If you are a marketer, you should probably avoid domains from these TLDs.
.us	United States entities.	Mixed reputation. Has appeared on some abused lists despite its intended use.

Views from the trenches

Best practices

Before registering a domain, research the TLD's reputation for spam and abuse rates.

Prioritize TLDs with strong abuse policies and historical stability, such as .com or .org.

Implement strong email authentication (SPF, DKIM, DMARC) to prove your legitimacy.

Regularly monitor your domain and IP reputation using available tools.

Common pitfalls

Choosing free or extremely cheap TLDs for primary sending domains.

Ignoring domain reputation reports and email deliverability metrics.

Sending unsolicited emails or using purchased email lists.

Assuming all TLDs are treated equally by spam filters.

Expert tips

Consider segmenting your email sending across multiple domains/TLDs if you have diverse sending needs, separating transactional from marketing emails.

Newer gTLDs might offer unique branding opportunities but often come with higher deliverability risks, especially for cold email.

Even if a TLD has a generally good reputation, poor sending practices on your part can still lead to deliverability issues.

A spike in bounce rates or spam complaints after sending to a new segment could indicate issues with recipient email domains.

Marketer view

Marketer from Email Geeks says they have observed that if you email from a .edu domain, your emails always get inboxed. This perception highlights how certain TLDs are sometimes believed to have inherent inboxing advantages, regardless of actual sending practices.

2023-09-15 - Email Geeks

Expert view

Expert from Email Geeks says that Spamhaus data generally indicates .com as the most abused TLD in terms of the raw number of domains, even if the percentage of malicious domains is small.

2023-09-15 - Email Geeks

Navigating TLD reputation for optimal deliverability

The question of the most abused TLD for spam is complex, with answers varying depending on whether you consider raw numbers or abuse percentages. What is clear, however, is that some TLDs carry a higher risk of deliverability issues due to their historical association with spam and malicious activity.

As email senders, our goal is to ensure our messages reach the inbox reliably. While we cannot control the overall reputation of a TLD, we can choose reputable ones and maintain strong sending practices. This includes rigorous list hygiene, relevant content, and proper email authentication.

By staying informed about TLD reputations and focusing on building a positive sender score, you can navigate the complexities of email deliverability more effectively and protect your email program from unnecessary challenges.