How do hyperlinks in the body of an email affect deliverability?
Michael Ko
Co-founder & CEO, Suped
Published 30 May 2025
Updated 16 Aug 2025
6 min read
Hyperlinks are an indispensable part of almost any email, serving as the bridge that connects recipients to more information, products, or services. They drive engagement, conversions, and direct traffic to your digital properties. However, their presence isn't without implications for email deliverability.
Internet Service Providers (ISPs) and spam filters scrutinize every element of an email, and hyperlinks are no exception. They are closely examined for signs of malicious intent, spam, or poor sender practices. Understanding how links are perceived and handled by these systems is crucial to ensuring your emails consistently reach the inbox.
The anatomy of a link and its reputation
When we talk about hyperlinks, it’s not just the visible text, but the entire underlying URL that matters. The domain of the linked URL carries its own reputation, separate from your sending domain. If you link to a domain with a poor reputation, or one that's associated with spam or phishing, it can negatively impact your email's deliverability, even if your own sending domain is pristine.
Third-party links, those that point to domains you don't control, introduce additional risk. While necessary for sharing content from platforms like social media or news sites, these links can inadvertently associate your email with less reputable domains, especially if those domains are shared by other senders with bad practices. Always be mindful of the reputation of external domains you link to, as their standing can affect your own sender reputation.
Link tracking, while valuable for analytics, also changes the original URL. Email service providers often wrap your original links with their own tracking domains. While this is standard practice, the reputation of these tracking domains is paramount. Ensure your email service provider maintains a strong reputation for their tracking links. For a deeper dive into this, you might find our article on HTTP tracking links and deliverability helpful.
Quantity vs. quality: Is there a magic number?
A common question is whether there's a specific limit to how many links you can include. The truth is, it's less about the sheer number of hyperlinks and more about the context and recipient engagement. High-volume, legitimate email senders often include dozens of links in their emails without issue, particularly in newsletters or e-commerce promotions.
However, if you include many links and very few are clicked, that can signal disinterest from your audience or even suspicious behavior to spam filters. Filters look at engagement metrics as a strong indicator of an email's legitimacy. An email with unclicked links, whether many or few, can ultimately affect your sender reputation over time.
The balance lies in quality over quantity. An email with a few highly relevant and engaged links will perform better than one cluttered with many unclicked, low-value links. This focus on multiple or long links is a crucial aspect of overall email deliverability.
Link types that trigger spam filters
Certain types of hyperlinks are more likely to trigger spam filters. URL shorteners, like Bitly or TinyURL, are a prime example. While convenient, they have historically been abused by spammers to disguise malicious links, making them a red flag for many ISPs. Avoiding them is a smart move for your deliverability.
Another red flag is when the display text of a hyperlink doesn't match the actual URL, or when the URL is unencoded or contains suspicious characters. Spam filters look for inconsistencies and obfuscation as indicators of deceptive practices. Always ensure your visible link text clearly represents the destination, creating trust with both recipients and email filters.
Additionally, linking to domains that are frequently found on public or private blocklists can severely impact your deliverability (also known as blacklists). It's not enough to check your own IP or domain, but also the domains you link out to. You can find more information about this in our guide on what happens when your domain is on an email blacklist.
Best practices for hyperlinking
To ensure your hyperlinks aid deliverability rather than hinder it, stick to best practices. Always use descriptive and relevant anchor text for your links. This not only improves user experience but also provides context to spam filters about the linked content. Avoid generic calls to action like "click here" if possible, opting instead for something that clearly indicates the destination.
Consistency between your sending domain and the domains you link to builds trust. If you can, host all your linked content on your own website using your own domain. This approach, often referred to as self-hosted links, strengthens your brand's authority and reduces reliance on external domain reputations. Additionally, always use HTTPS for all your links, as it signals a secure connection and is a trust factor for both recipients and ISPs.
It's also essential to include a clear and functional unsubscribe link. This isn't just a compliance requirement, but a critical deliverability factor. Providing an easy way to opt-out improves subscriber engagement and reduces spam complaints, which are major reputation detractors. Make sure this link is visible and accessible, often placed in the footer.
Hyperlinks: a deliverability balancing act
Understanding how hyperlinks affect email deliverability is a balancing act. It's not about avoiding links, which would render your emails ineffective for most marketing or transactional purposes. Instead, it's about intelligent implementation and a keen awareness of the factors that influence how ISPs perceive your linked content.
By focusing on the quality and relevance of your links, maintaining a strong sender and linked domain reputation, and avoiding practices that trigger spam filters, you can ensure your hyperlinks enhance your email strategy without compromising deliverability. Consistent monitoring and adherence to these best practices will help your messages land where they belong: in the inbox.
Views from the trenches
Best practices
Always use descriptive and relevant anchor text for your hyperlinks, providing clear context.
Ensure consistency: link to content on your own domain whenever possible to build trust and control reputation.
Utilize HTTPS for all links to signal security and trustworthiness to email providers and recipients.
Place a clear, functional unsubscribe link in every email, typically in the footer, to manage engagement and prevent spam complaints.
Common pitfalls
Over-relying on URL shorteners, which are often associated with spam and can trigger filters.
Including a high number of links that receive very few clicks, signaling low engagement to ISPs.
Linking to third-party domains with poor or unknown reputations, which can inadvertently affect your sender score.
Using mismatched or obfuscated link text that doesn't clearly indicate the actual URL destination.
Expert tips
Monitor your linked domains' reputations regularly to preempt potential deliverability issues.
Prioritize engagement metrics for your links; high click-through rates signal healthy sender behavior.
Test your emails rigorously before sending to identify any link-related issues or render discrepancies.
Segment your audience and tailor the number and type of links to their specific interests for better performance.
Marketer view
Marketer from Email Geeks says the number of links is less likely to cause issues than if some of those links lead to bad places.
2022-07-07 - Email Geeks
Marketer view
Marketer from Email Geeks says that having many links can be more challenging for deliverability, but this depends on the setup; links from one brand are generally fine, but multiple brands can be problematic.
