Do all ESPs use redirects for click tracking?

Most reputable Email Service Providers (ESPs) automatically use redirects for click tracking. This is standard practice and generally does not harm deliverability because ESPs work to maintain the reputation of their tracking domains. The visible URL in the email is rewritten to pass through the ESP's server for data collection before redirecting to the final destination.

Can redirects lead to my domain being blocklisted?

Redirects can lead to your domain being blocklisted if the redirecting domain (e.g., a generic link shortener) or the final destination is associated with spam, phishing, or malware. ESP-managed redirects are less likely to cause this because reputable ESPs proactively monitor and maintain their tracking domains. The key is the reputation of all domains involved in the redirect chain.

How can I check if my redirect links are safe?

You can check your redirect links by manually clicking them to verify the final destination. For more advanced checks, you can use online tools that show the full redirect chain and check the reputation of each domain in the chain. Ensure all final landing pages are secure and reputable.

What's the difference between an ESP redirect and a URL shortener?

An ESP redirect is primarily for click tracking, where your ESP temporarily redirects clicks through its own domain to gather data. A URL shortener, on the other hand, is a tool that takes a long URL and generates a shorter one, often for ease of sharing. While both involve redirection, ESP redirects are typically optimized for deliverability by trusted providers, whereas generic URL shorteners can carry higher risks due to potential misuse by spammers.

Does using redirected URLs in email CTAs impact deliverability? - Sender reputation - Email deliverability - Knowledge base

When crafting email campaigns, the links you include in your calls to action (CTAs) are crucial for driving engagement. A common question arises about how using redirected URLs, especially those on a different domain or sub-domain than your sending address, might affect email deliverability. There's a prevailing idea that anything deviating from the 'clean' and 'consistent' approach of direct links could flag spam filters.

The reality is more nuanced than a simple yes or no. Many email service providers (ESPs) automatically employ redirects for click tracking and analytics. This means that even if you insert a direct link to your website, the URL your subscribers actually see or click might first route through a tracking domain before landing on your intended page.

Understanding how these redirects work and when they can become a problem is key to ensuring your emails consistently land in the inbox rather than the spam folder. We will explore the technical aspects, potential risks, and best practices for using redirected URLs in your email CTAs.

How email service providers handle links

Most email service providers (ESPs) or marketing automation platforms automatically rewrite the links in your emails to track clicks. This is a standard practice that allows them to gather valuable data on subscriber engagement, such as click-through rates and user behavior.

When an ESP rewrites a link, the original destination URL is embedded within a new tracking URL that belongs to the ESP. When a recipient clicks this rewritten link, they are first directed to the ESP's server, which logs the click, and then immediately redirects them to the final intended destination. This process is usually seamless and imperceptible to the user. You can learn more about how link shorteners interact with ESP click tracking in our guide on link shorteners and ESP click tracking.

Example of an ESP rewritten linkURL

http://click.your-esp.com/?longstringofcharacters/original-destination.com

Because this redirection occurs on the ESP's (or sending platform's) domain, it's generally considered benign. The reputation of the ESP's tracking domain is what matters most in these cases, and reputable ESPs work hard to maintain strong sender reputations for their tracking links. For a deeper understanding of URL alignment in these scenarios, you can read about how tracking URL subdomain alignment affects deliverability.

The nuance of sender reputation and domain alignment

While ESP-managed redirects are usually safe, the reputation of the redirecting domain and the final destination can still impact deliverability. If the redirecting domain (especially if it's not managed by a reputable ESP) or the ultimate landing page is associated with spam, phishing, or malware, it can lead to deliverability issues.

Email filters continuously evaluate various aspects of an email, including the sender's reputation, content, and the nature of any links it contains. Some advanced filters might occasionally follow redirect chains to inspect the final destination. If this destination is on a blocklist (or blacklist), your email could be flagged, even if the initial redirecting domain is clean. Our article on how link redirects affect email reputation provides more detail.

A key factor is perceived domain alignment. If your sending domain and the visible domain in the CTA link (before any ESP rewrite) are consistent, it builds trust. However, if you are manually creating redirects that don't align with your sending domain or use third-party shorteners without a strong reputation, you could be taking a risk. For a general overview of link impact, refer to this article on links hurting deliverability. Our guide on hyperlinks in email bodies and deliverability also offers valuable insights.

Best practices for link reputation

Maintain alignment: Ensure your sending domain has a strong reputation. If your ESP allows, use a custom tracking domain that is a subdomain of your primary sending domain.
Monitor landing pages: Always ensure the final destination of your links is secure, relevant, and not associated with any suspicious activity or blocklists.
Avoid excessive redirects: While ESP redirects are common, adding multiple layers of manual redirects on top of them can complicate things and potentially raise red flags.

Potential red flags and pitfalls

Not all redirects are created equal. While ESP-managed redirects for tracking are generally safe, certain types of redirected URLs can indeed harm your email deliverability. The primary concern is when redirects are used to obscure a malicious or low-quality final destination.

One common pitfall is the use of untrusted or generic link shorteners. While some popular services are reputable, many spammers use new or suspicious shortener domains to hide their true intentions. These generic shortener domains can quickly end up on blocklists, leading to your emails being rejected or sent to spam. Our detailed guide on how chained redirects affect deliverability further explains complex redirect scenarios.

Another issue arises from multiple redirects, sometimes called 'chained redirects.' Even if each individual redirect is harmless, too many redirects can be perceived as an attempt to obscure the final destination. This can make spam filters suspicious. It can also create a poor user experience, as it adds latency before the user reaches the intended page. This article from Email on Acid provides further perspective on excessive redirects.

Trusted redirects (generally safe)

ESP click tracking: Links are rewritten by a reputable email service provider like Mailchimp for performance tracking and analytics.
Branded short URLs: Custom branded links (e.g., yourbrand.link/product) that redirect to your main site, maintaining brand consistency and trust.
Internal site redirects: Using a redirect on your own domain (e.g., yourdomain.com/go/product) that resolves to another page on your domain or a trusted social media page.

Risky redirects (potential deliverability issues)

Generic link shorteners: Using unbranded, public link shorteners that are frequently abused by spammers and are prone to being blocklisted.
Chained redirects: Multiple layers of redirects before reaching the final destination, which can appear suspicious to filters and delay user experience.
Malicious redirects: Redirects designed to lead users to phishing sites, malware, or other illicit content, regardless of the initial domain.

Best practices for email CTA links

To ensure your redirected URLs don't negatively impact your email deliverability, focus on maintaining a strong sender reputation and adhering to general email marketing best practices. The goal is to build trust with internet service providers (ISPs) and email recipients, signaling that your emails are legitimate and valuable. For comprehensive solutions, refer to our guide on technical solutions for email deliverability.

Always use a reputable ESP for your email campaigns. These providers have sophisticated systems in place to manage link tracking, ensure proper domain alignment, and protect their sender reputation, which indirectly benefits yours. If you are struggling with emails going to spam, our article on why emails go to spam can offer solutions.

Regularly monitor your email deliverability metrics. Keep an eye on your open rates, click-through rates, and bounce rates. A sudden drop in engagement or an increase in bounces could indicate an issue, potentially related to how your links are perceived by recipients and ISPs. Understanding hidden factors impacting deliverability is important for accurate assessment. Also, consider the steps to increase email click through rate to improve overall engagement.

Link Type	Impact on Deliverability	Recommendation
ESP tracking redirect	Minimal to none, generally safe with reputable ESPs.	Use an ESP that manages its tracking domains well.
Branded short URL	Low impact if the domain has a good reputation and leads to trusted content.	Ideal for social media or concise links. Ensure the domain is dedicated and trustworthy.
Generic link shortener	High risk. Often associated with spam and blocklists, leading to poor deliverability.	Avoid using them in email marketing campaigns. Prioritize your custom tracking domains.
Chained redirects	Moderate risk. Can appear suspicious and degrade user experience due to latency.	Streamline your redirect paths. Use direct links or a single ESP-managed redirect.
Malicious redirects	Extremely high risk. Will lead to immediate blocklisting and severe reputation damage.	Never link to untrustworthy content. Ensure all links lead to secure and legitimate pages.

Views from the trenches

Best practices

Use your ESP's built-in click tracking capabilities, as they are optimized for deliverability.

Always ensure the final landing page destination is secure and free from any suspicious content.

Consider using a custom tracking domain (a subdomain of your main domain) with your ESP.

Regularly monitor your sender reputation and link reputation to identify potential issues early.

Common pitfalls

Using generic, public link shorteners that are often associated with spam and blocklists.

Implementing multiple manual redirect layers on top of ESP tracking, creating chained redirects.

Linking to untrustworthy or compromised websites, even if via a redirect.

Not aligning tracking domains with your sending domain, especially during sender warm-up.

Expert tips

Maintain consistent branding across your sending domain, tracking domain, and landing page domain.

Test your email links thoroughly before sending to ensure they resolve correctly and quickly.

Focus on the quality of your content and list hygiene; these are paramount for deliverability.

If using redirects, ensure the redirect server is properly configured and fast.

Expert view

Expert from Email Geeks says that ESP click tracking rewrites links, so the domain seen by the email client is not the original one and is unrelated to the from addresses, making redirects generally harmless.

2020-07-28 - Email Geeks

Marketer view

Marketer from Email Geeks says that while they were taught to keep things clean and consistent without outside URLs, especially during warm-up, they weren't sure if using a redirect would bypass this concern.

2020-07-28 - Email Geeks

Summary

In conclusion, using redirected URLs in email CTAs does not inherently impact deliverability negatively, especially when these redirects are managed by reputable email service providers for click tracking purposes. These systems are designed to ensure seamless tracking without triggering spam filters.

The critical factors that influence deliverability are the overall sender reputation, the reputation of the redirecting domain (if not an ESP's tracking domain), and crucially, the reputation and security of the final destination URL. Avoid using generic, untrusted link shorteners or creating complex, chained redirects. By focusing on these elements, you can confidently use redirected URLs in your email CTAs without jeopardizing your inbox placement.