The Hidden Cost of a Bad TLD: Why Your Domain Impacts More Than Just Branding
When launching a startup, choosing the right domain name is one of the most critical branding decisions. While factors like availability, creativity, and cost often take priority, the long-term impact of domain selection—especially on email deliverability—is frequently overlooked.
Some businesses that start with tertiary TLDs like .fun or .pump encounter serious issues with spam filtering, email blacklisting, and lost communications. These problems can create significant roadblocks as a company scales, affecting customer trust, investor relations, and overall business operations.
If you thought all domain endings were created equal, think again. Some TLDs have become hotspots for spam, phishing, and botnet activity—and Spamhaus is keeping score.
The TLDs Leading in Spam & Botnet Abuse
If you thought all domain endings were created equal, think again. Some TLDs have become hotspots for spam, phishing, and botnet activity—and Spamhaus is keeping score.
As of early 2025, here are some of the most abused or rapidly rising TLDs for spam and malicious behavior:
- .top: Experienced a 974% increase in botnet command and control (C&C) activity between July and December 2024, indicating a substantial rise in malicious use.
- .sbs: Entered the top five most abused TLDs with a 252% increase in botnet C&C domains during the same period.
- .online: Re-entered the charts with a 280% increase in abuse, ranking second among the most abused TLDs.
When registering a domain, it’s worth checking whether the TLD has a spammy reputation. Not all endings are equal in the eyes of email filters (or your visitors' trust).
The Email Problem Most Businesses Don’t Anticipate
A domain name isn’t just for a website—it directly impacts the ability to send and receive emails reliably.
Common Issues with Lesser-Known TLDs:
- Spam Filters Are Aggressive – Many tertiary TLDs have a high association with spam, increasing the likelihood that emails from these domains will land in junk folders or be blocked entirely.
- Blacklists Can Block Communication – Certain domains have poor reputations with major email providers, making it difficult to reach inboxes.
- Misrouted Emails = Missed Opportunities – Customers and business partners often default to emailing the .com version of a domain, leading to lost messages and potential revenue.
Why a Premium Domain Matters
A strong, reputable TLD—such as .com, .co, or well-established industry-specific domains like .ai—offers clear advantages beyond branding:
- Higher Email Deliverability – A trusted domain increases the chances of emails reaching inboxes instead of spam folders.
- Fewer Lost Messages – Users naturally assume a .com address, ensuring critical emails aren’t accidentally sent to the wrong recipient.
- Enhanced Brand Trust – A premium domain signals legitimacy and professionalism, fostering confidence among customers, investors, and partners.
The Challenges of Fixing a Poor Domain Choice
Businesses experiencing email issues due to a tertiary TLD have a few potential solutions:
- Acquiring the premium version of the domain (if available) and transitioning branding accordingly.
- Implementing email authentication protocols (SPF, DKIM, DMARC) to improve email deliverability and reduce spam filtering.
- Using a trusted email provider like Google Workspace to help mitigate the effects of a less reputable TLD.
- Monitoring blacklists to ensure the domain isn’t flagged and taking necessary corrective actions if it is (we use MXToolBox.com)
However, these fixes can be time-consuming, costly, and not always fully effective. The most reliable strategy is securing a high-quality domain from the outset to avoid these issues altogether.
A Strong Domain is a Smart Investment
A domain name is more than just a digital address—it’s a foundation for business credibility, communication, and long-term success. Choosing a tertiary TLD may seem like a minor compromise, but the hidden costs can be substantial.
For businesses looking to build lasting brands, securing a premium domain is a strategic decision that prevents future headaches, ensures reliable communication, and strengthens brand authority. Investing in the right domain early on sets the stage for sustainable growth and success.
