List-Unsubscribe Header: Why It’s a Big Deal

List unsubscribe header cover image with tiles

List-unsubscribe headers have become a more common and expected feature in email marketing, driven by industry best practices and legal requirements worldwide. Most major mailbox providers now support list-unsubscribe headers to varying degrees, with some displaying visible unsubscribe links and others processing them behind the scenes. 

And the use of list-unsubscribe headers is only likely to continue growing as they provide a user-friendly way for email recipients to manage their subscriptions.

In this detailed guide, we explain how this feature works and the numerous advantages of implementing it in your email marketing campaigns.

List-Unsubscribe Header: What is it?

The list-unsubscribe header is part of an email header that provides a standardized way for email recipients to unsubscribe from mailing lists. Including this header in an email allows email clients to display an “Unsubscribe” option at the top of an email, typically near the sender’s email address or the subject line. 

List unsubscribe header
List unsubscribe header

This feature makes it easier for recipients to opt out of receiving further emails from a particular mailing list without having to navigate to a separate unsubscription page or reply to the email with an unsubscribe request.

By providing a standard way to handle unsubscribes, the list-unsubscribe header aims to improve the user experience. It also has a benefit for email marketers — it reduces the chances of recipients marking emails as spam when they wish to stop receiving messages

It’s a win-win for both senders and recipients, as the list-unsubscribe header encourages responsible and user-friendly email marketing practices.

Why was the List-Unsubscribe Header Created?

The creation of the list-unsubscribe header is the result of a collaborative effort within the email industry to establish standards that benefit both senders and recipients. By adopting a consistent approach to unsubscribes, email providers and marketers can work together to create a more trustworthy and user-friendly email ecosystem.

Before the implementation of list-unsubscribe headers to handle unsubscribes, users often had to scroll through emails desperately seeking unsubscribe links. If that sounds bad, the second option was much worse — email users would have to visit external websites and find a page where they could opt out of mailing lists. The list-unsubscribe header streamlines this process by providing a clear and straightforward method for users to unsubscribe without exiting their email client.

Before these headers existed, users who struggled to unsubscribe from emails would resort to marking messages as spam. It was simpler than finding an unsubscribe link for many. By making the unsubscribe process more straightforward, the list-unsubscribe header aims to reduce the number of legitimate emails being marked as spam, which is favorable to marketers.

Additionally, many countries and regions have regulations in place governing email marketing practices, which often dictate that senders provide a clear and easy way for recipients to opt out of future communications. The list-unsubscribe header helps email senders comply with such regulations by offering a standardized method for handling unsubscribes.

Over the past few years, this feature has also seen widespread adoption. 

The list of mailbox providers that support list-unsubscribe header includes:

  • Apple Mail
  • Gmail
  • Outlook
  • Yahoo Mail
  • Microsoft 365

Introduced to enhance the overall email experience for users, this header addition cut down on the rate of legitimate emails being marked as spam, and encouraged email senders to comply with regulations.

Why List-Unsubscribe Headers are Important for Email Marketers

You might be thinking: “I’ve already included an unsubscribe link further down the email, why should I include one at the top, the first thing a reader will see? Why tempt them to opt out?”

The reason you should provide a list-unsubscribe header is — the moment your email recipient decides to bail, there’s no stopping them. And if this person struggles to find the unsubscribe option, they’re going to go for the next best option: Report as spam.

Between the two, you’d rather have your subscribers choose to unsubscribe. This is because mailbox providers take spam reports more seriously than unsubscribes, so you want to avoid them as much as you can. In an extreme scenario, excessive spam reports can even get you kicked off your own email services platform.

So let’s sum it up:

  1. List-unsubscribe headers show your reader you’re confident in the value you provide.
  2. Adding a list-unsubscribe header improves your sender score, and in the process, improves your deliverability rate. It’s safe to assume mailbox providers greatly appreciate you including a list-unsubscribe header.
  3. It’s not just your sender reputation that gets a bump; your subscribers will also appreciate you offering them an easy out.
  4. Including a list-unsubscribe header makes you seem professional and your company reliable.
  5. It’s easy to implement.
  6. Compliance requires you to provide a list-unsubscribe header.
  7. Do you really want to email uninterested subscribers? Not only does that boost your operational costs but it’s also bad for your engagement when your recipients delete your emails without reading them.

Let’s now learn more about how this feature functions.

List-Unsubscribe Header: How it Works

The list-unsubscribe header provides a standardized way for email recipients to unsubscribe from mailing lists directly from their email clients. 

There are two ways of including a list-unsubscribe header — the mailto method, where users can unsubscribe by sending an email, and the URL method, where recipients can unsubscribe by visiting a link. We will explain these in detail shortly, but here’s how a typical email recipient experiences the list-unsubscribe header.

Here’s a general overview of how the feature works:

  1. For the feature to work, the list-unsubscribe header must be a part of the email headers. One or more URLs can be added to this header, pointing to the unsubscribe web pages for the mailing list. If the mailto method is used, an email address must be configured to receive unsubscription requests.
  2. When this email reaches recipients, their email clients process the list-unsubscribe header information.
  3. Email clients that support the list-unsubscribe header integrate this information into their user interface. This often results in the display of an “Unsubscribe” or similar option within the email client itself.
  4. When a recipient decides to unsubscribe from the mailing list, they click on this Unsubscribe option.
  5. Clicking it triggers the URL or activates the email link specified in the list-unsubscribe header. 
  6. Depending on the mailing list’s configuration, the recipient may be directed to a web page where they can confirm their desire to unsubscribe or they will be asked to send an unsubscription email to the address you specified. 
  7. The unsubscribe process, whether through a confirmation page or an automated removal, is carried out. 
  8. Finally, the recipient’s email address is taken off the mailing list.

By providing a standardized mechanism for unsubscribing, the list-unsubscribe header streamlines the process for recipients, making it easier for them to manage their email preferences and lowering the chances of them marking your emails as spam. 

Which Mailbox Providers Support List-Unsubscribe Headers?

Before you implement list-unsubscribe headers, you might be wondering — do the major mailbox providers even support it? 

Here’s a list of the more renowned names that do, alongside the unsubscribe method:

Mailbox providerMailto methodURL method
Gmail app on iOS and Android
Yahoo! Mail
Apple Mail on macOS
Apple Mail on iOS
Mailbox providers that support list-unsubscribe headers

Considering Gmail, Apple Mail, and Outlook serve about 92% of the global email market, we’d say yes; it does make sense to implement list-unsubscribe headers in your emails!

How to Add a List-Unsubscribe Header to Your Emails

Adding a list-unsubscribe header to your emails involves modifying the email headers before sending them. And you have two ways of doing this — you can use the mailto method or the URL method. If you wish to offer an easy unsubscribe option in your email headers, you can implement one, or both, of the two methods.

The Mailto Method 

To use the Mailto method, you must first create a unique e-mail address for unsubscribe requests; ensure you reserve this account purely for unsubscriptions. The list-unsubscribe header in your emails will include this email address. 

When recipients click on the “Unsubscribe” option in their email client, it opens their default email application with a pre-filled email to the address/addresses you specified. Once they press send, you will receive their unsubscribe request.

Typically, the code inserted into the header looks like this: “List-Unsubscribe: <mailto:unsubscribe@yourcompany.com>”

List unsubscribe Mailto method
List unsubscribe Mailto method

If you use this method to deal with unsubscribes, you must constantly monitor the inbox so you can promptly honor the requests that come in.

Here’s a table comparing the pros and cons of Mailto method:

More popular and hence more familiar to users.In a few cases, the mailto method may skip the confirmation step, potentially leading to accidental unsubscribes.
It is simple to implement.The unsubscribe email account needs constant monitoring.
Immediate initiation of an unsubscribe request from a recipient.
Has widespread acceptance among mailbox providers
Pros and Cons of using the mailto method in list-unsubscribe headers

Now let’s examine the second type of list-unsubscribe header.

The URL Method

The method is slowly building up in popularity these days, and here’s how it works.

For the URL method, you will have to create a landing page with a form/radio buttons for the unsubscription process. The list-unsubscribe header in your emails will lead users to this page to unsubscribe them. 

To add this feature, here is the snippet of code you will have to include in the header: “List-Unsubscribe: <https://yourcompany.com/unsubscribe>”

List unsubscribe URL method
List unsubscribe URL method

When recipients click on the unsubscribe link in their email clients, the link will lead them to the web page you created where they can confirm and complete the unsubscription. You can also allow immediate removal without confirmation. Ensure users don’t need to log in on this page because that can be aggravating for people looking to quickly unsubscribe.

Regardless of the method you choose, it’s a good idea to send feedback to the recipients, providing information about the unsubscribe action. This email can include details about the success of the unsubscribe request plus you can express regret to see them go.

Let’s look at the pros and cons of the URL method of list-unsubscribe headers:

The URL method may be more popular with users due to immediate confirmation of unsubscription.Select users may dislike being sent to a web page for unsubscription.
You can create customized unsubscribe processes.Is more complicated to create, as compared to the mailto method.
Good opportunity to collect feedback — the reason for unsubscribing. 
Pros and Cons of using the URL method in list-unsubscribe headers

Now that you know about both methods, let’s explore how to add this amazing feature to your emails.

Setting Up List-Unsubscribe Headers on Your Email Services Platform 

So you’ve locked the method of list-unsubscribe you wish to use — good job!

Here are the steps to follow next.

  1. On your email platform, locate the page where you can add custom headers to your emails. This is usually an option in your settings page, SMTP server settings, or in the code if you’re sending emails via custom software.
  2. Insert the list-unsubscribe header into the email headers. The header will be either a URL or an email address, depending on the unsubscribe method you choose. You can (and should) include both.
  3. It’s now time to test if the feature works correctly. Send test emails to yourself and verify that the unsubscribe option works as expected.
  4. The success of the list-unsubscribe header depends on email client support for the feature. And since there’s always a chance it could fail or work incorrectly, add alternative methods for recipients to unsubscribe, such as a clear and visible unsubscribe link within the email body. 

Another added benefit of list-unsubscribe headers is that most mailbox providers see them in a positive light. Next, let’s look at how popular mailbox services treat list-unsubscribe headers.

List-Unsubscribe Headers in Gmail

Gmail seems to love list-unsubscribe headers; as one of the most popular mailbox providers with a user-first approach, it makes sense. Gmail introduced the feature in 2014, under the name of Auto-Unsubscribe.

Gmail Web version
Gmail Web version
Gmail App on Android
Gmail App on Android
Gmail App on iOS
Gmail App on iOS

As Gmail preps to fight spammers with renewed energy, it’s making the list-unsubscribe header mandatory for senders, from 2024 onwards. It’s part of their campaign to focus on sender reputation a lot more to fight the spam menace — if you email more than 5,000 Gmail users in a day, the company wants you to implement security protocols and make it easier for consumers to opt out. 

Gmail already supports it on these platforms:

  • Web-version (Gmail.com).
  • Gmail app on Android.
  • Gmail app on iOS.

Google insists that senders implement this feature ASAP; they want subscribers to be able to unsubscribe with a single click in the near future.

Gmail supports both mailto and URL methods of list-unsubscribe headers

List-Unsubscribe Header in Outlook

Outlook also supports list-unsubscribe headers, but only of the mailto variety.

When Outlook detects a mailto link, it displays an “Unsubscribe” link next to the sender’s email when a list-unsubscribe header is present. The below image indicates the presence of a list-unsubscribe header in the code of an email.

Outlook on Mac
Outlook on Mac

Microsoft is known to evaluate your sender score before showing your email to their service users, so even if the feature may not always work, there is a deliverability benefit to including a list-unsubscribe header in your emails. 

List-Unsubscribe Header in Apple Mail

The list-unsubscribe header functionality in Apple Mail is in line with industry standards, providing users with a streamlined way to unsubscribe from mailing lists directly from their email clients — this applies to both iOS and macOS.

Mail App on iOS
Mail App on iOS
Apple Mail App on macOS
Apple Mail App on macOS

Apple Mail supports both the URL and mailto methods of the list-unsubscribe header. This allows you to include web-based URLs and/or email addresses in the header, giving your recipients flexibility in how they choose to unsubscribe.

If your email includes the list-unsubscribe header, Apple Mail displays an “Unsubscribe” option within the Mail app on an iPhone or a Mac computer, in a distinct banner, above the email body. On iOS, the banner is visible above your email address whereas on the Mac Mail app, the banner is below your sender details.

Users can then click on the “Unsubscribe” option, which triggers the specified unsubscribe mechanism — a web-based confirmation page or an email removal process. Apple Mail may provide feedback to the user or sender about the success of the unsubscribe action.

Dos and Don’ts for List-Unsubscribe Headers

If you’re wondering about best practices while implementing list-unsubscribe headers, we’ve got a list of dos and don’ts that should cover all the bases.


  1. Ensure your emails include clear and visible options for users to unsubscribe. This can include both the list-unsubscribe header and an easily accessible unsubscribe link within the email content.
  2. Include both web-based and email-based unsubscribe options in the list-unsubscribe header to cater to user preferences.
  3. Before sending emails to your entire mailing list, thoroughly test the unsubscribe functionality to ensure it works as expected across various email clients.
  4. Confirm that your unsubscribe mechanism and processes comply with relevant email marketing regulations, such as the CAN-SPAM Act, GDPR, or other applicable laws.
  5. Act promptly on unsubscribe requests and monitor any feedback or notifications provided by your email system regarding unsubscribe actions.
  6. If your unsubscribe process includes a confirmation step, clearly communicate this to users, and make it an optional step rather than mandatory.
  7. Include information in your emails that educates recipients about the purpose and functionality of the list-unsubscribe header, making it clear how they can manage their subscription preferences.


  1. Avoid using misleading language or deceptive practices in your unsubscribe options. Clearly communicate the purpose of the unsubscribe link or button.
  2. Do not hide or make it difficult for users to find the unsubscribe button. Make them easily accessible to enhance user experience.
  3. Don’t delay responding to unsubscribe requests. Ignoring unsubscribe requests can lead to user frustration and potential violations of regulations.
  4. Ensure the URLs provided in the list-unsubscribe header are valid and lead to functional unsubscribe mechanisms. Broken links can frustrate users and harm your sender reputation.
  5. While providing multiple unsubscribe methods is good, avoid overwhelming users with too many options. Keep it simple and user-friendly.
  6. Do not use the unsubscribe process as a method to trick users into performing actions they did not intend. This can harm your reputation and erode trust.

By following these dos and don’ts, you can implement list-unsubscribe headers responsibly, providing a positive experience for your email recipients while staying in compliance with regulations.

Campaign Refinery: In Favor of List-Unsubscribe Headers

We believe the sender-recipient relationship is a symbiotic connection, and should be treated with respect. When you add a list-unsubscribe header to your emails, you are showing respect to your recipients for their time and attention. 

We feel you should build a list of subscribers who are wholly interested in receiving your content. That is also why we recommend you use the double opt-in method when onboarding new prospects.

The best part of adding the list-unsubscribe header feature is that it keeps recipients away from the “Report spam” button. Spam reports can rapidly drag down your sender reputation

At Campaign Refinery, we are strongly in favor of marketers following best practices to ensure your sender score never takes a hit, and including a list-unsubscribe header definitely counts as a huge plus. 

Besides this feature, here are additional tips to improve your deliverability:

  • Constantly monitor your IP and domain reputation,
  • Send relevant content,
  • Segment your audience well,
  • Clean your email lists,
  • Implement security protocols on your domain,
  • Work with a reputable email platform.

When it comes to deliverability, there are no two ways about it — our deliverability rates crush the competition. 

To experience what it’s like to see your inboxing rates skyrocket, sign up to become a Campaign Refinery customer today!

Similar Posts