Are URL shorteners like bit.ly bad for email deliverability?

Key findings

• Reputation risk: Public URL shorteners, such as Bit.ly, are frequently used by spammers and phishers, which taints their shared domain reputation. This poor reputation can then negatively impact the deliverability of legitimate emails that use these services.
• Transparency issues: Shortened URLs hide the true destination link, making it challenging for email recipients and automated spam filters to trust the link. This lack of visibility increases the likelihood of emails being sent to the spam folder or being blocked entirely.
• Increased scrutiny: Mailbox providers, like Gmail, are increasingly wary of generic shortened URLs and may actively block them or route them to spam, irrespective of the sender's individual reputation. This is why Gmail has started blocking URL shorteners.
• Redirection layers: When an email sending platform already wraps links for click tracking, adding a URL shortener introduces an additional layer of redirection. Each extra redirect can create a point of failure or increase suspicion from filters. For more on this, check out our guide on how link redirects affect email reputation.

Key considerations

• Avoid public shorteners: It is generally advisable to avoid using public URL shorteners for email marketing campaigns to protect your sender reputation.
• Use custom branded domains: If shortening is necessary, consider using a custom branded domain for your links. This allows you to build and maintain your own domain reputation, rather than relying on a shared one. See our article on how URL shorteners and domain reputation impact deliverability.
• Direct links are best: Whenever possible, use direct, full-length URLs. This provides the most transparency to recipients and spam filters, fostering trust and improving deliverability.
• Check your links: Regularly check the status of your links (and sending domains) on various email blocklists and blacklists. This proactive approach helps identify and address any reputation issues quickly, as discussed by SMTP2GO in their article on URL shorteners.

Key opinions

• Deliverability risk: Many marketers view generic URL shorteners as detrimental to email deliverability, often citing their association with spam and phishing activities.
• Reputation concerns: The shared nature of these shortener domains means their reputation can be easily tainted, impacting all users, including legitimate senders. This can lead to your domain being blacklisted.
• Trust issues: Recipients often hesitate to click on shortened links because they can't immediately see the destination, leading to reduced engagement.
• Avoidance is best: A common sentiment is to avoid URL shorteners entirely if possible, especially for critical communications like transactional emails, as emphasized by EasySendy Pro.

Key considerations

• Prioritize transparency: Marketers should prioritize transparent links that clearly show the destination, building recipient trust and improving deliverability.
• Custom domains for tracking: If link tracking is needed, using a custom tracking domain (often provided by ESPs) is preferred over third-party URL shorteners. You can learn more about how link shorteners impact deliverability with ESP click tracking.
• Impact on campaign success: The potential for reduced deliverability due to shortened links can severely impact the effectiveness of email marketing campaigns.

Key opinions

• Long-standing risk: Experts acknowledge that the deliverability risks associated with public URL shorteners like Bit.ly have been a consistent problem for over a decade.
• Abuse vulnerability: Public link shorteners, especially those with publicly accessible APIs, are susceptible to abuse by spammers, which rapidly degrades their collective reputation.
• Hidden destinations: The concealed nature of shortened links makes it challenging for spam filters to assess the legitimacy of the destination, leading to higher filtering rates.
• Private vs. public: While public shorteners are problematic, experts note that private or custom link shorteners can be acceptable if properly secured against abuse.

Key considerations

• Secure custom shorteners: If using a custom shortener, ensure it cannot be exploited to redirect users to arbitrary domains. It should only redirect to your own controlled pages.
• Avoid excessive redirects: Each additional redirect layer (e.g., ESP tracking, then a shortener) adds a potential point of failure and can raise flags with mail filters. Consider the impact on your email domain reputation.
• Transparency is key: For optimal deliverability, links should be as transparent as possible, clearly indicating their destination to both recipients and automated systems. This is an ongoing challenge for email deliverability, as detailed by Word to the Wise.

Key findings

• Security vulnerabilities: Official security advisories and user reports consistently link URL shortening services to potential security vulnerabilities and scams, making them risky for email use.
• User hesitation: Research indicates that users are hesitant to click on shortened URLs because they cannot immediately ascertain the final destination, which can also be exploited by malicious actors.
• Abuse potential: Even legitimate URL shortening services can be abused by bad actors to hide harmful websites, leading to their domains being associated with spam and phishing activities.
• Filter flags: Email filters are programmed to flag links that obscure their true destination, treating them as suspicious regardless of the sender's intent. This includes issues like how unencoded URLs impact deliverability.

Key considerations

• Direct linking preference: Documentation often implies a preference for direct, fully transparent URLs in email content to ensure optimal deliverability and user trust.
• Sender reputation management: To maintain a strong sender reputation, it's critical to avoid elements in emails that are commonly associated with spam, such as generic shortened links. This is a fundamental aspect of improving email deliverability.
• Consider alternatives: If space or aesthetics are a concern, look into branded custom domains or verify that your email service provider's click tracking mechanism uses your domain, which is typically safer than third-party shorteners.