Link shorteners offer a tempting solution for creating cleaner, more concise URLs, especially in character-limited environments like social media. The appeal extends to email marketing, where a neat link might seem more professional or less intimidating than a long, complex URL.
However, when it comes to email deliverability, the use of link shorteners, particularly public ones, introduces a layer of complexity and potential risk that many marketers overlook. The question isn't just about aesthetics, but about trust, reputation, and whether your emails will reach the inbox at all.
While there are scenarios where they might seem beneficial, the reality is that in most email marketing contexts, they can negatively impact your sender reputation and lead to your messages being flagged as spam. Understanding why this happens is crucial for maintaining strong email performance.
The hidden risks of public link shorteners
The primary reason public link shorteners, such as Bitly or TinyURL, are problematic in email marketing stems from their ability to obscure the final destination of a link. This characteristic, while convenient for shortening, is frequently exploited by spammers and phishers to hide malicious URLs.
Email spam filters are designed to protect recipients from harmful content. When they encounter a shortened link from a shared, public domain, it raises a red flag because the ultimate landing page isn't immediately visible. This lack of transparency can lead to your emails being marked as suspicious, regardless of the content's legitimacy. Research indicates that indiscriminate use of these shorteners can raise red flags for email spam filters.
Furthermore, recipients themselves are increasingly wary of unfamiliar or generic shortened links. Many internet users are aware that these types of URLs are often used in phishing attempts, leading to a natural distrust. This can result in lower click-through rates and, in some cases, recipients manually marking your email as spam, further damaging your sender reputation. The practice is often used by spammers or phishing schemes.
Public shorteners a red flag
Using public link shortening services such as Bitly or TinyURL can significantly harm your email deliverability. These shared domains are often abused by spammers, leading to poor reputation scores with email service providers (ESPs) and increased chances of your emails landing in the spam folder.
Public versus branded shorteners: a matter of trust
It's important to differentiate between generic, public link shorteners and branded, custom domain shorteners. While both technically shorten a URL, the key distinction lies in domain ownership and, consequently, trust and reputation management.
A branded shortener uses your own domain, or a specific subdomain of it, (e.g., links.yourdomain.com/yourlink) instead of a generic one like bit.ly/yourlink. This maintains brand consistency and allows you to build and control the reputation of that specific domain. Understanding how URL shorteners impact domain reputation is key.
While branded shorteners still involve a redirect, the crucial difference is that the visible domain belongs to you, not a shared third-party service. This provides a clear signal to both recipients and spam filters about the legitimacy and origin of the link, reducing suspicion and improving the likelihood of successful delivery.
Public shorteners
Reputation risk: Shared domains mean reputation is impacted by other users.
Spam flags: Higher likelihood of triggering spam filters.
Branded shorteners
Reputation control: Your own domain builds and maintains its unique reputation.
Brand consistency: Links align with your brand, fostering trust.
Improved deliverability: Less likely to be flagged by filters due to known domain.
Enhanced analytics: Often provide more granular tracking data.
Impact on sender reputation and deliverability
The impact on your sender reputation is one of the most critical aspects. Internet Service Providers (ISPs) like Gmail and Outlook meticulously analyze every element within an email, including the links. If a shortened link resolves to a domain with a poor reputation or one that's frequently associated with spam, it casts a negative shadow on your entire email.
Public link shortener domains are frequently added to email blacklists (or blocklists) due to widespread abuse by malicious actors. Once a domain is on such a blacklist, any email containing links from it faces an uphill battle to reach the inbox. This can bring your email marketing campaign to a standstill, effectively ruining your email marketing campaign. If you want to know what happens when your domain is blocklisted, there's a guide for that.
Even if the final destination URL is legitimate and safe, the initial shortened URL acts as a gateway. If this gateway is perceived as risky by spam filters or email providers, your email might be junked or filtered before the recipient even has a chance to see the content. This is why some anti-spam entities and certification programs explicitly advise against or even prohibit their use to improve email deliverability and prevent spam issues.
Best practices and alternatives for safer linking
Given the significant risks associated with public link shorteners, it's generally best to avoid them entirely in your email marketing campaigns. Instead, focus on using direct, clear links that explicitly show the destination domain. This transparency builds trust with your recipients and helps spam filters assess the legitimacy of your content more accurately.
For tracking purposes, most reputable email service providers (ESPs) offer their own robust click-tracking mechanisms. These often use a subdomain of your primary sending domain or a dedicated tracking domain that you own and control. This approach is much safer because you maintain the reputation of that specific tracking domain, rather than relying on a shared one. To learn more, read our article do link shorteners impact deliverability with ESP click tracking.
If character limits or aesthetic preferences absolutely necessitate a shorter URL, invest in a branded link shortening service that allows you to use your own custom domain. This provides the brevity you seek without the inherent shared reputation risks of public shorteners. This way, the link still aligns with your brand and contributes positively to your overall domain reputation.
Views from the trenches
Best practices
Always align your brand and domain across all elements within your emails, including link domains.
Utilize your own dedicated domains for all URLs to maintain control over their reputation.
Implement branded link shortening platforms that you exclusively own and manage.
Common pitfalls
Relying on public link shorteners like Bitly or TinyURL can severely degrade deliverability.
Using shared generic domains for shortened URLs exposes your email program to the misbehavior of other users.
Ignoring the domain reputation of your links can lead to increased spam classifications.
Expert tips
Certification programs often prohibit the use of public link shorteners due to their inherent risks.
Understand that even if a link shortener uses popular infrastructure, if it's not branded to your domain, it carries risk.
Focus on consistency in your domain usage, as inbox providers prioritize this for trust signals.
Marketer view
Marketer from Email Geeks says: It is generally better to use a branded or white-labeled link shortener with your sending domain, as spam filters primarily rely on reputation, and you control your own domain's reputation.
2021-03-17 - Email Geeks
Expert view
Expert from Email Geeks says: Old information regarding Bitly causing blocks is still largely valid, highlighting the long-standing issues with shared shortener domains.
2021-03-17 - Email Geeks
Navigating links for better email deliverability
While link shorteners offer convenience and a clean aesthetic, their use in email marketing, particularly public variants, poses significant risks to your email deliverability and sender reputation. The masking of destination URLs and the shared nature of public shortener domains make them targets for spam filters and can lead to your legitimate emails being misclassified.
To ensure your emails consistently reach the inbox, prioritize transparency and control over your links. Using direct links, leveraging your ESP's branded click tracking, or investing in a custom branded link shortener are all superior strategies. These approaches safeguard your sender reputation, build recipient trust, and ultimately contribute to more successful email marketing campaigns. For further assistance on deliverability, check our guide on email deliverability issues.
Bitly or 
TinyURL, are problematic in email marketing stems from their ability to obscure the final destination of a link. This characteristic, while convenient for shortening, is frequently exploited by spammers and phishers to hide malicious URLs.
Gmail and 
Outlook meticulously analyze every element within an email, including the links. If a shortened link resolves to a domain with a poor reputation or one that's frequently associated with spam, it casts a negative shadow on your entire email.
